diff --git a/.version b/.version
new file mode 100644
index 0000000..cd5ac03
--- /dev/null
+++ b/.version
@@ -0,0 +1 @@
+2.0
diff --git a/README.md b/README.md
index 541e92e..b1c426c 100644
--- a/README.md
+++ b/README.md
@@ -1 +1,349 @@
-# bash-fun
\ No newline at end of file
+# Introduction
+
+[Introduction to fun.sh library](http://ssledz.github.io/presentations/bash-fun.html#/)
+
+# Quick start
+
+```bash
+#!/bin/bash
+. <(test -e fun.sh || curl -Ls https://raw.githubusercontent.com/ssledz/bash-fun/master/src/fun.sh > fun.sh; cat fun.sh)
+
+seq 1 4 | sum
+```
+
+# Functions overview
+|||||||
+|------|------|------|------|------|------|
+|**plus**|**append**|**buff**|**curry**|**div**|**drop**|
+|**factorial**|**filter**|**foldl**|**foldr**|**head**|**join**|
+|**lambda**|**last**|**list**|**map**|**mod**|**mul**|
+|**prepend**|**product**|**ret**|**revers_str**|**revers**|**scanl**|
+|**splitc**|**strip**|**sub**|**sum**|**tail**|**take**|
+|**catch**|**try**|**tupl**|**tupr**|**tup**|**tupx**|
+|**unlist**|**zip**|**λ**|**with_trampoline**|**res**|**call**|
+
+## *list/unlist*
+
+```bash
+$ list 1 2 3
+1
+2
+3
+
+$ list 1 2 3 4 5 | unlist
+1 2 3 4 5
+```
+
+## *take/drop/tail/head/last*
+
+```bash
+$ list 1 2 3 4 | drop 2
+3
+4
+
+$ list 1 2 3 4 5 | head
+1
+
+$ list 1 2 3 4 | tail
+2
+3
+4
+
+$ list 1 2 3 4 5 | last
+5
+
+$ list 1 2 3 4 5 | take 2
+1
+2
+```
+
+## *join*
+
+```bash
+$ list 1 2 3 4 5 | join ,
+1,2,3,4,5
+
+$ list 1 2 3 4 5 | join , [ ]
+[1,2,3,4,5]
+```
+
+## *map*
+
+```bash
+$ seq 1 5 | map λ a . 'echo $((a + 5))'
+6
+7
+8
+9
+10
+
+$ list a b s d e | map λ a . 'echo $a$(echo $a | tr a-z A-Z)'
+aA
+bB
+sS
+dD
+eE
+```
+
+## *flat map*
+
+```bash
+$ seq 2 3 | map λ a . 'seq 1 $a' | join , [ ]
+[1,2,1,2,3]
+
+$ list a b c | map λ a . 'echo $a; echo $a | tr a-z A-z' | join , [ ]
+[a,A,b,B,c,C]
+```
+
+## *filter*
+
+```bash
+$ seq 1 10 | filter λ a . '[[ $(mod $a 2) -eq 0 ]] && ret true || ret false'
+2
+4
+6
+8
+10
+```
+
+## *foldl/foldr*
+
+```bash
+$ list a b c d | foldl λ acc el . 'echo -n $acc-$el'
+a-b-c-d
+
+$ list '' a b c d | foldr λ acc el .\
+    'if [[ ! -z $acc ]]; then echo -n $acc-$el; else echo -n $el; fi'
+d-c-b-a
+```
+
+```bash
+$ seq 1 4 | foldl λ acc el . 'echo $(($acc + $el))'
+10
+```
+
+```bash
+$ seq 1 4 | foldl λ acc el . 'echo $(mul $(($acc + 1)) $el)'
+64 # 1 + (1 + 1) * 2 + (4 + 1) * 3 + (15 + 1) * 4 = 64
+
+$ seq 1 4 | foldr λ acc el . 'echo $(mul $(($acc + 1)) $el)'
+56 # 1 + (1 + 1) * 4 + (8 + 1) * 3 + (27 + 1) * 2 = 56
+```
+
+## *tup/tupx/tupl/tupr*
+
+```bash
+$ tup a 1
+(a,1)
+
+$ tup 'foo bar' 1 'one' 2
+(foo bar,1,one,2)
+
+$ tup , 1 3
+(u002c,1,3)
+```
+
+```bash
+$ tupl $(tup a 1)
+a
+
+$ tupr $(tup a 1)
+1
+
+$ tup , 1 3 | tupl
+,
+
+$ tup 'foo bar' 1 'one' 2 | tupl
+foo bar
+
+$ tup 'foo bar' 1 'one' 2 | tupr
+2
+```
+
+```bash
+$ tup 'foo bar' 1 'one' 2 | tupx 2
+1
+
+$ tup 'foo bar' 1 'one' 2 | tupx 1,3
+foo bar
+one
+
+$ tup 'foo bar' 1 'one' 2 | tupx 2-4
+1
+one
+2
+```
+
+## *buff*
+
+```bash
+$ seq 1 10 | buff λ a b . 'echo $(($a + $b))'
+3
+7
+11
+15
+19
+
+$ seq 1 10 | buff λ a b c d e . 'echo $(($a + $b + $c + $d + $e))'
+15
+40
+```
+
+## *zip*
+
+```bash
+$ list a b c d e f | zip $(seq 1 10)
+(a,1)
+(b,2)
+(c,3)
+(d,4)
+(e,5)
+(f,6)
+```
+
+```bash
+$ list a b c d e f | zip $(seq 1 10) | last | tupr
+6
+```
+
+## *curry*
+
+```bash
+add2() {
+    echo $(($1 + $2))
+}
+```
+
+```bash
+$ curry inc add2 1
+```
+
+```bash
+$ inc 2
+3
+
+$ seq 1 3 | map λ a . 'inc $a'
+2
+3
+4
+```
+
+## *try/catch*
+
+```bash
+$ echo 'expr 2 / 0' | try λ _ . 'echo 0'
+0
+
+$ echo 'expr 2 / 0' | try λ status . 'echo $status'
+2
+
+$ echo 'expr 2 / 2' | try λ _ . 'echo 0'
+1
+```
+
+```bash
+try λ  _ . 'echo some errors during pull; exit 1' < <(echo git pull)
+```
+
+```bash
+$ echo 'expr 2 / 0' \
+    | LANG=en catch λ cmd status val . 'echo cmd=$cmd,status=$status,val=$val'
+cmd=expr 2 / 0,status=2,val=(expr:,division,by,zero)
+```
+
+```bash
+$ echo 'expr 2 / 2' | catch λ _ _ val . 'tupl $val'
+1
+```
+
+## *scanl*
+
+```bash
+$ seq 1 5 | scanl lambda acc el . 'echo $(($acc + $el))'
+1
+3
+6
+10
+15
+```
+
+```bash
+$ seq 1 5 | scanl lambda a b . 'echo $(($a + $b))' | last
+15
+```
+
+## *with_trampoline/res/call*
+
+```bash
+factorial() {
+    fact_iter() {
+        local product=$1
+        local counter=$2
+        local max_count=$3
+        if [[ $counter -gt $max_count ]]; then
+            res $product
+        else
+            call fact_iter $(echo $counter\*$product | bc) $(($counter + 1)) $max_count
+        fi
+    }
+
+    with_trampoline fact_iter 1 1 $1
+}
+```
+
+```bash
+$ time factorial 30 | fold -w 70
+265252859812191058636308480000000
+
+real    0m1.854s
+user    0m0.072s
+sys     0m0.368s
+```
+
+```bash
+time factorial 60 | fold -w 70
+8320987112741390144276341183223364380754172606361245952449277696409600
+000000000000
+
+real    0m3.635s
+user    0m0.148s
+sys     0m0.692s
+```
+
+```bash
+$ time factorial 90 | fold -w 70
+1485715964481761497309522733620825737885569961284688766942216863704985
+393094065876545992131370884059645617234469978112000000000000000000000
+
+real    0m4.371s
+user    0m0.108s
+sys     0m0.436s
+```
+
+# Examples
+
+```bash
+processNames() {
+
+  uppercase() {
+     local str=$1
+     echo $(tr 'a-z' 'A-Z' <<< ${str:0:1})${str:1}
+  }
+
+  list $@ \
+    | filter λ name . '[[ ${#name} -gt 1 ]] && ret true || ret false' \
+    | map λ name . 'uppercase $name' \
+    | foldl λ acc el . 'echo $acc,$el'
+
+}
+
+processNames adam monika s slawek d daniel Bartek j k
+```
+
+```bash
+Adam,Monika,Slawek,Daniel,Bartek
+```
+
+
+# Resources
+* [Inspiration](https://quasimal.com/posts/2012-05-21-funsh.html)
\ No newline at end of file
diff --git a/examples/example.sh b/examples/example.sh
index 3fe7026..80cb792 100755
--- a/examples/example.sh
+++ b/examples/example.sh
@@ -57,4 +57,103 @@ curry add3 add 3
 add3 9
 
 list a b c d | foldl lambda acc el . 'echo -n $acc-$el'
-list '' a b c d | foldr lambda acc el . 'if [[ ! -z $acc ]]; then echo -n $acc-$el; else echo -n $el; fi'
\ No newline at end of file
+list '' a b c d | foldr lambda acc el . 'if [[ ! -z $acc ]]; then echo -n $acc-$el; else echo -n $el; fi'
+
+seq 1 4 | foldl lambda acc el . 'echo $(($acc + $el))'
+
+#1 - 2 - 3 - 4
+seq 1 4 | foldl lambda acc el . 'echo $(($acc - $el))'
+#1 - 4 - 3 - 2
+seq 1 4 | foldr lambda acc el . 'echo $(($acc - $el))'
+
+#1 + (1 + 1) * 2 + (4 + 1) * 3 + (15 + 1) * 4 = 64
+
+seq 1 4 | foldl lambda acc el . 'echo $(mul $(($acc + 1)) $el)'
+
+#1 + (1 + 1) * 4 + (8 + 1) * 3 + (27 + 1) * 2 = 56
+seq 1 4 | foldr lambda acc el . 'echo $(mul $(($acc + 1)) $el)'
+
+tup a 1
+tupl $(tup a 1)
+tupr $(tup a 1)
+tup a 1 | tupl
+tup a 1 | tupr
+
+seq 1 10 | buff lambda a b . 'echo $(($a + $b))'
+echo 'XX'
+seq 1 10 | buff lambda a b c d e . 'echo $(($a + $b + $c + $d + $e))'
+
+list a b c d e f | zip $(seq 1 10)
+
+echo
+list a b c d e f | zip $(seq 1 10) | last | tupr
+
+arg='[key1=value1,key2=value2,key3=value3]'
+get() {
+  local pidx=$1
+  local idx=$2
+  local arg=$3
+  echo $arg | tr -d '[]' | cut -d',' -f$idx | cut -d'=' -f$pidx
+}
+
+curry get_key get 1
+curry get_value get 2
+
+get_key 1 $arg
+get_value 1 $arg
+
+seq 1 3 | map lambda a . 'tup $(get_key $a $arg) $(get_value $a $arg)'
+
+echo 'ls /home' | try λ cmd status ret . 'echo $cmd [$status]; echo $ret'
+echo '/home' | try λ cmd status ret . 'echo $cmd [$status]; echo $ret'
+
+seq 1 5 | scanl lambda a b . 'echo $(($a + $b))'
+seq 1 5 | scanl lambda a b . 'echo $(($a + $b))' | last
+
+seq 2 3 | map lambda a . 'seq 1 $a' | join , [ ]
+list a b c | map lambda a . 'echo $a; echo $a | tr a-z A-z' | join , [ ]
+
+echo 0 | cat - <(curl -s https://raw.githubusercontent.com/ssledz/bash-fun/v1.1.1/src/fun.sh) | \
+    map lambda a . 'list $a' | foldl lambda acc el . 'echo $(($acc + 1))'
+
+echo 0 | cat - <(curl -s curl -s https://raw.githubusercontent.com/ssledz/bash-fun/v1.1.1/src/fun.sh) \
+            | foldl lambda acc el . 'echo $(($acc + 1))'
+
+
+factorial() {
+    fact_iter() {
+        local product=$1
+        local counter=$2
+        local max_count=$3
+        if [[ $counter -gt $max_count ]]; then
+            echo $product
+        else
+            fact_iter $(echo $counter\*$product | bc) $(($counter + 1)) $max_count
+        fi
+    }
+
+    fact_iter 1 1 $1
+}
+
+factorial_trampoline() {
+    fact_iter() {
+        local product=$1
+        local counter=$2
+        local max_count=$3
+        if [[ $counter -gt $max_count ]]; then
+            res $product
+        else
+            call fact_iter $(echo $counter\*$product | bc) $(($counter + 1)) $max_count
+        fi
+    }
+
+    with_trampoline fact_iter 1 1 $1
+}
+
+echo Factorial test
+
+time factorial 30
+time factorial_trampoline 30
+
+time factorial 60
+time factorial_trampoline 60
\ No newline at end of file
diff --git a/release.sh b/release.sh
new file mode 100755
index 0000000..219af38
--- /dev/null
+++ b/release.sh
@@ -0,0 +1,47 @@
+#!/bin/bash
+
+version=$(cat .version)
+
+release_version=${version%%-SNAPSHOT}
+new_version=$(echo $release_version+0.1 | bc)
+
+[[ $? -ne 0 ]] && echo 'Error exiting.' && exit 1
+
+snapshot_version=${new_version}-SNAPSHOT
+
+cat <<EOF
+
+    current version     : $version
+    release version     : $release_version
+    new snapshot version: $snapshot_version
+
+EOF
+
+git fetch
+
+echo start the release by creating a new release branch
+
+git checkout -b release/$release_version origin/develop
+echo $release_version > ./.version
+git add ./.version
+git commit -m "[release] prepare release v$release_version"
+git tag v$release_version
+echo $snapshot_version > ./.version
+git add ./.version
+git commit -m "[release] prepare for next development iteration"
+
+echo merge the version back into develop
+git checkout develop
+git merge --no-ff -m "[release] merge release/$release_version into develop" release/$release_version
+
+git checkout master
+echo merge the version back into master but use the tagged version instead of the release/$releaseVersion HEAD
+git merge --no-ff -m "[release] merge previous version into master to avoid the increased version number" release/$release_version~1
+
+echo get back on the develop branch
+git checkout develop
+echo finally push everything
+git push origin develop master
+git push --tags
+echo removing the release branch
+git branch -D release/$release_version
diff --git a/src/fun.sh b/src/fun.sh
index 14c5979..9608852 100755
--- a/src/fun.sh
+++ b/src/fun.sh
@@ -119,7 +119,7 @@ mul() {
   ( set -f; echo $(($1 * $2)) )
 }
 
-add() {
+plus() {
   echo $(($1 + $2))
 }
 
@@ -167,16 +167,22 @@ revers_str() {
   cat - | splitc | revers | join
 }
 
-try() {
+catch() {
   local f="$@"
   local cmd=$(cat -)
-  ret="$(2>&1 $cmd)"
-  local status=$?
-  list "$cmd" $status $(list $ret | join \#) | $f
+  local val=$(2>&1 eval "$cmd"; echo $?)
+  local cnt=$(list $val | wc -l)
+  local status=$(list $val | last)
+  $f < <(list "$cmd" $status $(list $val | take $((cnt - 1)) | unlist | tup))
+}
+
+try() {
+  local f="$@"
+  catch lambda cmd status val . '[[ $status -eq 0 ]] && tupx 1- $val | unlist || { '"$f"' < <(list $status); }'
 }
 
 ret() {
-  echo $1
+  echo $@
 }
 
 filter() {
@@ -187,16 +193,26 @@ filter() {
   done
 }
 
+stripl() {
+  local arg=$1
+  cat - | map lambda l . 'ret ${l##'$arg'}'
+}
+
+stripr() {
+  local arg=$1
+  cat - | map lambda l . 'ret ${l%%'$arg'}'
+}
+
 strip() {
   local arg=$1
-  cat - | map lambda l . 'ret ${l##'$arg'}' | map lambda l . 'ret ${l%%'$arg'}'
+  cat - | stripl "$arg" | stripr "$arg"
 }
 
 buff() {
   local cnt=-1
   for x in $@; do
     [[ $x = '.' ]] && break
-    cnt=$(add $cnt 1)
+    cnt=$(plus $cnt 1)
   done
   local args=''
   local i=$cnt
@@ -209,7 +225,13 @@ buff() {
 }
 
 tup() {
-  list "$@" | join , '(' ')'
+  if [[ $# -eq 0 ]]; then
+    local arg
+    read arg
+    tup $arg
+  else
+    list "$@" | map lambda x . 'echo ${x/,/u002c}' | join , '(' ')'
+  fi
 }
 
 tupx() {
@@ -220,7 +242,7 @@ tupx() {
   else
     local n=$1
     shift
-    list "$@" | strip '\(' | strip '\)' | unlist | cut -d',' -f${n}
+    echo "$@" | stripl '(' | stripr ')' | cut -d',' -f${n} | tr ',' '\n' | map lambda x . 'echo ${x/u002c/,}'
   fi
 }
 
@@ -229,7 +251,7 @@ tupl() {
 }
 
 tupr() {
-  tupx 2 "$@"
+  tupx 1- "$@" | last
 }
 
 zip() {
@@ -241,7 +263,7 @@ zip() {
   done
 }
 
-function curry() {
+curry() {
   exportfun=$1; shift
   fun=$1; shift
   params=$*
@@ -252,3 +274,25 @@ function curry() {
   eval $cmd
 }
 
+with_trampoline() {
+  local f=$1; shift
+  local args=$@
+  while [[ $f != 'None' ]]; do
+    ret=$($f $args)
+#    echo $ret
+    f=$(tupl $ret)
+    args=$(echo $ret | tupx 2- | tr ',' ' ')
+  done
+  echo $args
+}
+
+res() {
+    local value=$1
+    tup "None" $value
+}
+
+call() {
+    local f=$1; shift
+    local args=$@
+    tup $f $args
+}
diff --git a/test/append_test.sh b/test/append_test.sh
new file mode 100755
index 0000000..e6ceb99
--- /dev/null
+++ b/test/append_test.sh
@@ -0,0 +1,15 @@
+#! /bin/bash
+
+testAppendToEmptyList() {
+  assertEquals 4 "$(list | append 4)"
+}
+
+testAppendToOneElementList() {
+  assertEquals "1 4" "$(list 1 | append 4 | unlist)"
+}
+
+testAppendToList() {
+  assertEquals "1 2 3 4 5 4" "$(list 1 2 3 4 5 | append 4 | unlist)"
+}
+
+. ./shunit2-init.sh
\ No newline at end of file
diff --git a/test/catch_test.sh b/test/catch_test.sh
new file mode 100755
index 0000000..b3f0917
--- /dev/null
+++ b/test/catch_test.sh
@@ -0,0 +1,19 @@
+#! /bin/bash
+
+testCatchIfSuccess() {
+  assertEquals 1 "$(echo 'expr 2 / 2' | catch lambda cmd status val . '[[ $status -eq 0 ]] && tupl $val || echo 0')"
+}
+
+testCatchIfError() {
+  assertEquals 0 $(echo 'expr 2 / 0' | catch lambda cmd status val . '[[ $status -eq 0 ]] && tupl $val || echo 0')
+  assertEquals 'cmd=expr 2 / 0,status=2,val=(expr:,division,by,zero)' "$(echo 'expr 2 / 0' | echo 'expr 2 / 0' | LANG=en catch lambda cmd status val . 'echo cmd=$cmd,status=$status,val=$val')"
+}
+
+testCatchEdgeCases() {
+  assertEquals 1 "$(echo 'expr 2 / 2' | catch lambda _ _ val . 'tupl $val')"
+  assertEquals 'expr 2 / 2' "$(echo 'expr 2 / 2' | catch lambda cmd . 'ret $cmd')"
+  assertEquals 'expr 2 / 2,0' "$(echo 'expr 2 / 2' | catch lambda cmd status . 'ret $cmd,$status')"
+  assertEquals 'expr 2 / 0,2' "$(echo 'expr 2 / 0' | catch lambda cmd status . 'ret $cmd,$status')"
+}
+
+. ./shunit2-init.sh
\ No newline at end of file
diff --git a/test/drop_test.sh b/test/drop_test.sh
new file mode 100755
index 0000000..5aef523
--- /dev/null
+++ b/test/drop_test.sh
@@ -0,0 +1,23 @@
+#! /bin/bash
+
+testDrop9From10() {
+  assertEquals 10 $(list {1..10} | drop 9)
+}
+
+testDrop8From10() {
+  assertEquals "9 10" "$(list {1..10} | drop 8 | unlist)"
+}
+
+testDropAll() {
+  assertEquals "" "$(list {1..10} | drop 10)"
+}
+
+testDropMoreThanAvailable() {
+  assertEquals "" "$(list {1..10} | drop 15)"
+}
+
+testDropZero() {
+  assertEquals "1 2 3 4 5 6 7 8 9 10" "$(list {1..10} | drop 0 | unlist)"
+}
+
+. ./shunit2-init.sh
\ No newline at end of file
diff --git a/test/head_test.sh b/test/head_test.sh
new file mode 100755
index 0000000..3ea2a7f
--- /dev/null
+++ b/test/head_test.sh
@@ -0,0 +1,16 @@
+#! /bin/bash
+
+testHeadFromList() {
+  assertEquals 1 $(list {1..10} | head)
+  assertEquals 5 $(list 5 6 7 | head)
+}
+
+testHeadFromOneElementList() {
+  assertEquals 1 $(list 1 | head)
+}
+
+testHeadFromEmptyList() {
+  assertEquals "" "$(list | head)"
+}
+
+. ./shunit2-init.sh
\ No newline at end of file
diff --git a/test/lambda_test.sh b/test/lambda_test.sh
new file mode 100755
index 0000000..4f05094
--- /dev/null
+++ b/test/lambda_test.sh
@@ -0,0 +1,38 @@
+#! /bin/bash
+
+testLambdaNoArguments_ifNoInput() {
+    assertEquals 'Hi there' "$(echo | lambda . 'echo Hi there')"
+}
+
+testLambdaNoArguments_ifSomeInputArguments() {
+    assertEquals 'Hi there' "$(echo 'xx\nyy\nzz' | lambda . 'echo Hi there')"
+}
+
+testLambdaOneArgument() {
+  identity() {
+    lambda x . '$x'
+  }
+  assertEquals "hi there !" "$(identity <<< 'echo hi there !')"
+  assertEquals 3 $(lambda x . 'echo $(($x + 1))' <<< '2')
+  assertEquals "hi there !" "$(λ x . 'echo $x' <<< 'hi there !')"
+}
+
+testLambdaSymbolTwoArguments() {
+    assertEquals 3 $(echo -e '1\n2' | lambda x y . 'echo $(($x + $y))')
+    assertEquals 5 $(echo -e '7\n2' | λ x y . 'echo $(($x - $y))')
+}
+
+testLambdaSymbolManyArguments() {
+    assertEquals 5 $(echo -e '1\n2\n3\n4\n5' | lambda a b c d e . 'echo $(($a + $b + $c + $d - $e))')
+}
+
+testLambdaSymbolManyArguments_ifInsufficientNumberOfArgumentsInLambda() {
+    assertEquals 6 $(echo -e '1\n2\n3\n4\n5' | lambda a b c . 'echo $(($a + $b + $c))')
+}
+
+testLambdaSymbolManyArguments_ifInsufficientNumberOfInputArguments() {
+    echo -e '1\n2' | lambda a b c d e . 'echo $(($a + $b + $c + $d + $e))' 2> /dev/null \
+        && fail "There should be syntax error"
+}
+
+. ./shunit2-init.sh
\ No newline at end of file
diff --git a/test/last_test.sh b/test/last_test.sh
new file mode 100755
index 0000000..e76a694
--- /dev/null
+++ b/test/last_test.sh
@@ -0,0 +1,16 @@
+#! /bin/bash
+
+testLastFromList() {
+  assertEquals 10 $(list {1..10} | last)
+  assertEquals 7 $(list 5 6 7 | last)
+}
+
+testLastFromOneElementList() {
+  assertEquals 1 $(list 1 | last)
+}
+
+testLastFromEmptyList() {
+  assertEquals "" "$(list | last)"
+}
+
+. ./shunit2-init.sh
\ No newline at end of file
diff --git a/test/lib/shflags b/test/lib/shflags
new file mode 100644
index 0000000..70cdea4
--- /dev/null
+++ b/test/lib/shflags
@@ -0,0 +1,1222 @@
+# vim:et:ft=sh:sts=2:sw=2
+#
+# Copyright 2008-2017 Kate Ward. All Rights Reserved.
+# Released under the Apache License 2.0 license.
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# shFlags -- Advanced command-line flag library for Unix shell scripts.
+# https://github.com/kward/shflags
+#
+# Author: kate.ward@forestent.com (Kate Ward)
+#
+# This module implements something like the gflags library available
+# from https://github.com/gflags/gflags.
+#
+# FLAG TYPES: This is a list of the DEFINE_*'s that you can do.  All flags take
+# a name, default value, help-string, and optional 'short' name (one-letter
+# name). Some flags have other arguments, which are described with the flag.
+#
+# DEFINE_string: takes any input, and interprets it as a string.
+#
+# DEFINE_boolean: does not take any arguments. Say --myflag to set
+#   FLAGS_myflag to true, or --nomyflag to set FLAGS_myflag to false. For short
+#   flags, passing the flag on the command-line negates the default value, i.e.
+#   if the default is true, passing the flag sets the value to false.
+#
+# DEFINE_float: takes an input and interprets it as a floating point number. As
+#   shell does not support floats per-se, the input is merely validated as
+#   being a valid floating point value.
+#
+# DEFINE_integer: takes an input and interprets it as an integer.
+#
+# SPECIAL FLAGS: There are a few flags that have special meaning:
+#   --help (or -?)  prints a list of all the flags in a human-readable fashion
+#   --flagfile=foo  read flags from foo.  (not implemented yet)
+#   --              as in getopt(), terminates flag-processing
+#
+# EXAMPLE USAGE:
+#
+#   -- begin hello.sh --
+#   #! /bin/sh
+#   . ./shflags
+#   DEFINE_string name 'world' "somebody's name" n
+#   FLAGS "$@" || exit $?
+#   eval set -- "${FLAGS_ARGV}"
+#   echo "Hello, ${FLAGS_name}."
+#   -- end hello.sh --
+#
+#   $ ./hello.sh -n Kate
+#   Hello, Kate.
+#
+# CUSTOMIZABLE BEHAVIOR:
+#
+# A script can override the default 'getopt' command by providing the path to
+# an alternate implementation by defining the FLAGS_GETOPT_CMD variable.
+#
+# NOTES:
+#
+# * Not all systems include a getopt version that supports long flags. On these
+#   systems, only short flags are recognized.
+
+#==============================================================================
+# shFlags
+#
+# Shared attributes:
+#   flags_error:  last error message
+#   flags_output: last function output (rarely valid)
+#   flags_return: last return value
+#
+#   __flags_longNames: list of long names for all flags
+#   __flags_shortNames: list of short names for all flags
+#   __flags_boolNames: list of boolean flag names
+#
+#   __flags_opts: options parsed by getopt
+#
+# Per-flag attributes:
+#   FLAGS_<flag_name>: contains value of flag named 'flag_name'
+#   __flags_<flag_name>_default: the default flag value
+#   __flags_<flag_name>_help: the flag help string
+#   __flags_<flag_name>_short: the flag short name
+#   __flags_<flag_name>_type: the flag type
+#
+# Notes:
+# - lists of strings are space separated, and a null value is the '~' char.
+#
+### ShellCheck (http://www.shellcheck.net/)
+# $() are not fully portable (POSIX != portable).
+#   shellcheck disable=SC2006
+# [ p -a q ] are well defined enough (vs [ p ] && [ q ]).
+#   shellcheck disable=SC2166
+
+# Return if FLAGS already loaded.
+[ -n "${FLAGS_VERSION:-}" ] && return 0
+FLAGS_VERSION='1.2.3pre'
+
+# Return values that scripts can use.
+FLAGS_TRUE=0
+FLAGS_FALSE=1
+FLAGS_ERROR=2
+
+# Logging levels.
+FLAGS_LEVEL_DEBUG=0
+FLAGS_LEVEL_INFO=1
+FLAGS_LEVEL_WARN=2
+FLAGS_LEVEL_ERROR=3
+FLAGS_LEVEL_FATAL=4
+__FLAGS_LEVEL_DEFAULT=${FLAGS_LEVEL_WARN}
+
+# Determine some reasonable command defaults.
+__FLAGS_EXPR_CMD='expr --'
+__FLAGS_UNAME_S=`uname -s`
+if [ "${__FLAGS_UNAME_S}" = 'BSD' ]; then
+  __FLAGS_EXPR_CMD='gexpr --'
+else
+  _flags_output_=`${__FLAGS_EXPR_CMD} 2>&1`
+  if [ $? -eq ${FLAGS_TRUE} -a "${_flags_output_}" = '--' ]; then
+    # We are likely running inside BusyBox.
+    __FLAGS_EXPR_CMD='expr'
+  fi
+  unset _flags_output_
+fi
+
+# Commands a user can override if desired.
+FLAGS_EXPR_CMD=${FLAGS_EXPR_CMD:-${__FLAGS_EXPR_CMD}}
+FLAGS_GETOPT_CMD=${FLAGS_GETOPT_CMD:-getopt}
+
+# Specific shell checks.
+if [ -n "${ZSH_VERSION:-}" ]; then
+  setopt |grep "^shwordsplit$" >/dev/null
+  if [ $? -ne ${FLAGS_TRUE} ]; then
+    _flags_fatal 'zsh shwordsplit option is required for proper zsh operation'
+  fi
+  if [ -z "${FLAGS_PARENT:-}" ]; then
+    _flags_fatal "zsh does not pass \$0 through properly. please declare' \
+\"FLAGS_PARENT=\$0\" before calling shFlags"
+  fi
+fi
+
+# Can we use built-ins?
+( echo "${FLAGS_TRUE#0}"; ) >/dev/null 2>&1
+if [ $? -eq ${FLAGS_TRUE} ]; then
+  __FLAGS_USE_BUILTIN=${FLAGS_TRUE}
+else
+  __FLAGS_USE_BUILTIN=${FLAGS_FALSE}
+fi
+
+
+#
+# Constants.
+#
+
+# Reserved flag names.
+__FLAGS_RESERVED_LIST=' ARGC ARGV ERROR FALSE GETOPT_CMD HELP PARENT TRUE '
+__FLAGS_RESERVED_LIST="${__FLAGS_RESERVED_LIST} VERSION "
+
+# Determined getopt version (standard or enhanced).
+__FLAGS_GETOPT_VERS_STD=0
+__FLAGS_GETOPT_VERS_ENH=1
+
+# shellcheck disable=SC2120
+_flags_getopt_vers() {
+  _flags_getopt_cmd_=${1:-${FLAGS_GETOPT_CMD}}
+  case "`${_flags_getopt_cmd_} -lfoo '' --foo 2>&1`" in
+    ' -- --foo') echo ${__FLAGS_GETOPT_VERS_STD} ;;
+    ' --foo --') echo ${__FLAGS_GETOPT_VERS_ENH} ;;
+    # Unrecognized output. Assuming standard getopt version.
+    *) echo ${__FLAGS_GETOPT_VERS_STD} ;;
+  esac
+  unset _flags_getopt_cmd_
+}
+# shellcheck disable=SC2119
+__FLAGS_GETOPT_VERS=`_flags_getopt_vers`
+
+# getopt optstring lengths
+__FLAGS_OPTSTR_SHORT=0
+__FLAGS_OPTSTR_LONG=1
+
+__FLAGS_NULL='~'
+
+# Flag info strings.
+__FLAGS_INFO_DEFAULT='default'
+__FLAGS_INFO_HELP='help'
+__FLAGS_INFO_SHORT='short'
+__FLAGS_INFO_TYPE='type'
+
+# Flag lengths.
+__FLAGS_LEN_SHORT=0
+__FLAGS_LEN_LONG=1
+
+# Flag types.
+__FLAGS_TYPE_NONE=0
+__FLAGS_TYPE_BOOLEAN=1
+__FLAGS_TYPE_FLOAT=2
+__FLAGS_TYPE_INTEGER=3
+__FLAGS_TYPE_STRING=4
+
+# Set the constants readonly.
+__flags_constants=`set |awk -F= '/^FLAGS_/ || /^__FLAGS_/ {print $1}'`
+for __flags_const in ${__flags_constants}; do
+  # Skip certain flags.
+  case ${__flags_const} in
+    FLAGS_HELP) continue ;;
+    FLAGS_PARENT) continue ;;
+  esac
+  # Set flag readonly.
+  if [ -z "${ZSH_VERSION:-}" ]; then
+    readonly "${__flags_const}"
+    continue
+  fi
+  case ${ZSH_VERSION} in
+    [123].*) readonly "${__flags_const}" ;;
+    *) readonly -g "${__flags_const}" ;;  # Declare readonly constants globally.
+  esac
+done
+unset __flags_const __flags_constants
+
+#
+# Internal variables.
+#
+
+# Space separated lists.
+__flags_boolNames=' '     # Boolean flag names.
+__flags_longNames=' '     # Long flag names.
+__flags_shortNames=' '    # Short flag names.
+__flags_definedNames=' '  # Defined flag names (used for validation).
+
+__flags_columns=''  # Screen width in columns.
+__flags_level=0     # Default logging level.
+__flags_opts=''     # Temporary storage for parsed getopt flags.
+
+#------------------------------------------------------------------------------
+# Private functions.
+#
+
+# Logging functions.
+_flags_debug() {
+  [ ${__flags_level} -le ${FLAGS_LEVEL_DEBUG} ] || return
+  echo "flags:DEBUG $*" >&2
+}
+_flags_info() {
+  [ ${__flags_level} -le ${FLAGS_LEVEL_INFO} ] || return
+  echo "flags:INFO $*" >&2
+}
+_flags_warn() {
+  [ ${__flags_level} -le ${FLAGS_LEVEL_WARN} ] || return
+  echo "flags:WARN $*" >&2
+}
+_flags_error() {
+  [ ${__flags_level} -le ${FLAGS_LEVEL_ERROR} ] || return
+  echo "flags:ERROR $*" >&2
+}
+_flags_fatal() {
+  [ ${__flags_level} -le ${FLAGS_LEVEL_FATAL} ] || return
+  echo "flags:FATAL $*" >&2
+  exit ${FLAGS_ERROR}
+}
+
+# Get the logging level.
+flags_loggingLevel() { echo ${__flags_level}; }
+
+# Set the logging level.
+#
+# Args:
+#   _flags_level_: integer: new logging level
+# Returns:
+#   nothing
+flags_setLoggingLevel() {
+  [ $# -ne 1 ] && _flags_fatal "flags_setLevel(): logging level missing"
+  _flags_level_=$1
+  [ "${_flags_level_}" -ge "${FLAGS_LEVEL_DEBUG}" \
+    -a "${_flags_level_}" -le "${FLAGS_LEVEL_FATAL}" ] \
+      || _flags_fatal "Invalid logging level '${_flags_level_}' specified."
+  __flags_level=$1
+  unset _flags_level_
+}
+
+# Define a flag.
+#
+# Calling this function will define the following info variables for the
+# specified flag:
+#   FLAGS_flagname - the name for this flag (based upon the long flag name)
+#   __flags_<flag_name>_default - the default value
+#   __flags_flagname_help - the help string
+#   __flags_flagname_short - the single letter alias
+#   __flags_flagname_type - the type of flag (one of __FLAGS_TYPE_*)
+#
+# Args:
+#   _flags_type_: integer: internal type of flag (__FLAGS_TYPE_*)
+#   _flags_name_: string: long flag name
+#   _flags_default_: default flag value
+#   _flags_help_: string: help string
+#   _flags_short_: string: (optional) short flag name
+# Returns:
+#   integer: success of operation, or error
+_flags_define() {
+  if [ $# -lt 4 ]; then
+    flags_error='DEFINE error: too few arguments'
+    flags_return=${FLAGS_ERROR}
+    _flags_error "${flags_error}"
+    return ${flags_return}
+  fi
+
+  _flags_type_=$1
+  _flags_name_=$2
+  _flags_default_=$3
+  _flags_help_=${4:-§}  # Special value '§' indicates no help string provided.
+  _flags_short_=${5:-${__FLAGS_NULL}}
+
+  _flags_debug "type:${_flags_type_} name:${_flags_name_}" \
+      "default:'${_flags_default_}' help:'${_flags_help_}'" \
+      "short:${_flags_short_}"
+
+  _flags_return_=${FLAGS_TRUE}
+  _flags_usName_="`_flags_underscoreName "${_flags_name_}"`"
+
+  # Check whether the flag name is reserved.
+  _flags_itemInList "${_flags_usName_}" "${__FLAGS_RESERVED_LIST}"
+  if [ $? -eq ${FLAGS_TRUE} ]; then
+    flags_error="flag name (${_flags_name_}) is reserved"
+    _flags_return_=${FLAGS_ERROR}
+  fi
+
+  # Require short option for getopt that don't support long options.
+  if [ ${_flags_return_} -eq ${FLAGS_TRUE} \
+      -a "${__FLAGS_GETOPT_VERS}" -ne "${__FLAGS_GETOPT_VERS_ENH}" \
+      -a "${_flags_short_}" = "${__FLAGS_NULL}" ]
+  then
+    flags_error="short flag required for (${_flags_name_}) on this platform"
+    _flags_return_=${FLAGS_ERROR}
+  fi
+
+  # Check for existing long name definition.
+  if [ ${_flags_return_} -eq ${FLAGS_TRUE} ]; then
+    if _flags_itemInList "${_flags_usName_}" "${__flags_definedNames}"; then
+      flags_error="definition for ([no]${_flags_name_}) already exists"
+      _flags_warn "${flags_error}"
+      _flags_return_=${FLAGS_FALSE}
+    fi
+  fi
+
+  # Check for existing short name definition.
+  if [ ${_flags_return_} -eq ${FLAGS_TRUE} \
+      -a "${_flags_short_}" != "${__FLAGS_NULL}" ]
+  then
+    if _flags_itemInList "${_flags_short_}" "${__flags_shortNames}"; then
+      flags_error="flag short name (${_flags_short_}) already defined"
+      _flags_warn "${flags_error}"
+      _flags_return_=${FLAGS_FALSE}
+    fi
+  fi
+
+  # Handle default value. Note, on several occasions the 'if' portion of an
+  # if/then/else contains just a ':' which does nothing. A binary reversal via
+  # '!' is not done because it does not work on all shells.
+  if [ ${_flags_return_} -eq ${FLAGS_TRUE} ]; then
+    case ${_flags_type_} in
+      ${__FLAGS_TYPE_BOOLEAN})
+        if _flags_validBool "${_flags_default_}"; then
+          case ${_flags_default_} in
+            true|t|0) _flags_default_=${FLAGS_TRUE} ;;
+            false|f|1) _flags_default_=${FLAGS_FALSE} ;;
+          esac
+        else
+          flags_error="invalid default flag value '${_flags_default_}'"
+          _flags_return_=${FLAGS_ERROR}
+        fi
+        ;;
+
+      ${__FLAGS_TYPE_FLOAT})
+        if _flags_validFloat "${_flags_default_}"; then
+          :
+        else
+          flags_error="invalid default flag value '${_flags_default_}'"
+          _flags_return_=${FLAGS_ERROR}
+        fi
+        ;;
+
+      ${__FLAGS_TYPE_INTEGER})
+        if _flags_validInt "${_flags_default_}"; then
+          :
+        else
+          flags_error="invalid default flag value '${_flags_default_}'"
+          _flags_return_=${FLAGS_ERROR}
+        fi
+        ;;
+
+      ${__FLAGS_TYPE_STRING}) ;;  # Everything in shell is a valid string.
+
+      *)
+        flags_error="unrecognized flag type '${_flags_type_}'"
+        _flags_return_=${FLAGS_ERROR}
+        ;;
+    esac
+  fi
+
+  if [ ${_flags_return_} -eq ${FLAGS_TRUE} ]; then
+    # Store flag information.
+    eval "FLAGS_${_flags_usName_}='${_flags_default_}'"
+    eval "__flags_${_flags_usName_}_${__FLAGS_INFO_TYPE}=${_flags_type_}"
+    eval "__flags_${_flags_usName_}_${__FLAGS_INFO_DEFAULT}=\
+\"${_flags_default_}\""
+    eval "__flags_${_flags_usName_}_${__FLAGS_INFO_HELP}=\"${_flags_help_}\""
+    eval "__flags_${_flags_usName_}_${__FLAGS_INFO_SHORT}='${_flags_short_}'"
+
+    # append flag names to name lists
+    __flags_shortNames="${__flags_shortNames}${_flags_short_} "
+    __flags_longNames="${__flags_longNames}${_flags_name_} "
+    [ "${_flags_type_}" -eq "${__FLAGS_TYPE_BOOLEAN}" ] && \
+        __flags_boolNames="${__flags_boolNames}no${_flags_name_} "
+
+    # Append flag names to defined names for later validation checks.
+    __flags_definedNames="${__flags_definedNames}${_flags_usName_} "
+    [ "${_flags_type_}" -eq "${__FLAGS_TYPE_BOOLEAN}" ] && \
+        __flags_definedNames="${__flags_definedNames}no${_flags_usName_} "
+  fi
+
+  flags_return=${_flags_return_}
+  unset _flags_default_ _flags_help_ _flags_name_ _flags_return_ \
+      _flags_short_ _flags_type_ _flags_usName_
+  [ ${flags_return} -eq ${FLAGS_ERROR} ] && _flags_error "${flags_error}"
+  return ${flags_return}
+}
+
+# Underscore a flag name by replacing dashes with underscores.
+#
+# Args:
+#   unnamed: string: log flag name
+# Output:
+#   string: underscored name
+_flags_underscoreName() {
+  echo "$1" |tr '-' '_'
+}
+
+# Return valid getopt options using currently defined list of long options.
+#
+# This function builds a proper getopt option string for short (and long)
+# options, using the current list of long options for reference.
+#
+# Args:
+#   _flags_optStr: integer: option string type (__FLAGS_OPTSTR_*)
+# Output:
+#   string: generated option string for getopt
+# Returns:
+#   boolean: success of operation (always returns True)
+_flags_genOptStr() {
+  _flags_optStrType_=$1
+
+  _flags_opts_=''
+
+  for _flags_name_ in ${__flags_longNames}; do
+    _flags_usName_="`_flags_underscoreName "${_flags_name_}"`"
+    _flags_type_="`_flags_getFlagInfo "${_flags_usName_}" "${__FLAGS_INFO_TYPE}"`"
+    [ $? -eq ${FLAGS_TRUE} ] || _flags_fatal 'call to _flags_type_ failed'
+    case ${_flags_optStrType_} in
+      ${__FLAGS_OPTSTR_SHORT})
+        _flags_shortName_="`_flags_getFlagInfo \
+            "${_flags_usName_}" "${__FLAGS_INFO_SHORT}"`"
+        if [ "${_flags_shortName_}" != "${__FLAGS_NULL}" ]; then
+          _flags_opts_="${_flags_opts_}${_flags_shortName_}"
+          # getopt needs a trailing ':' to indicate a required argument.
+          [ "${_flags_type_}" -ne "${__FLAGS_TYPE_BOOLEAN}" ] && \
+              _flags_opts_="${_flags_opts_}:"
+        fi
+        ;;
+
+      ${__FLAGS_OPTSTR_LONG})
+        _flags_opts_="${_flags_opts_:+${_flags_opts_},}${_flags_name_}"
+        # getopt needs a trailing ':' to indicate a required argument
+        [ "${_flags_type_}" -ne "${__FLAGS_TYPE_BOOLEAN}" ] && \
+            _flags_opts_="${_flags_opts_}:"
+        ;;
+    esac
+  done
+
+  echo "${_flags_opts_}"
+  unset _flags_name_ _flags_opts_ _flags_optStrType_ _flags_shortName_ \
+      _flags_type_ _flags_usName_
+  return ${FLAGS_TRUE}
+}
+
+# Returns flag details based on a flag name and flag info.
+#
+# Args:
+#   string: underscored flag name
+#   string: flag info (see the _flags_define function for valid info types)
+# Output:
+#   string: value of dereferenced flag variable
+# Returns:
+#   integer: one of FLAGS_{TRUE|FALSE|ERROR}
+_flags_getFlagInfo() {
+  # Note: adding gFI to variable names to prevent naming conflicts with calling
+  # functions
+  _flags_gFI_usName_=$1
+  _flags_gFI_info_=$2
+
+  # Example: given argument usName (underscored flag name) of 'my_flag', and
+  # argument info of 'help', set the _flags_infoValue_ variable to the value of
+  # ${__flags_my_flag_help}, and see if it is non-empty.
+  _flags_infoVar_="__flags_${_flags_gFI_usName_}_${_flags_gFI_info_}"
+  _flags_strToEval_="_flags_infoValue_=\"\${${_flags_infoVar_}:-}\""
+  eval "${_flags_strToEval_}"
+  if [ -n "${_flags_infoValue_}" ]; then
+    # Special value '§' indicates no help string provided.
+    [ "${_flags_gFI_info_}" = ${__FLAGS_INFO_HELP} \
+        -a "${_flags_infoValue_}" = '§' ] && _flags_infoValue_=''
+    flags_return=${FLAGS_TRUE}
+  else
+    # See if the _flags_gFI_usName_ variable is a string as strings can be
+    # empty...
+    # Note: the DRY principle would say to have this function call itself for
+    # the next three lines, but doing so results in an infinite loop as an
+    # invalid _flags_name_ will also not have the associated _type variable.
+    # Because it doesn't (it will evaluate to an empty string) the logic will
+    # try to find the _type variable of the _type variable, and so on. Not so
+    # good ;-)
+    #
+    # Example cont.: set the _flags_typeValue_ variable to the value of
+    # ${__flags_my_flag_type}, and see if it equals '4'.
+    _flags_typeVar_="__flags_${_flags_gFI_usName_}_${__FLAGS_INFO_TYPE}"
+    _flags_strToEval_="_flags_typeValue_=\"\${${_flags_typeVar_}:-}\""
+    eval "${_flags_strToEval_}"
+    # shellcheck disable=SC2154
+    if [ "${_flags_typeValue_}" = "${__FLAGS_TYPE_STRING}" ]; then
+      flags_return=${FLAGS_TRUE}
+    else
+      flags_return=${FLAGS_ERROR}
+      flags_error="missing flag info variable (${_flags_infoVar_})"
+    fi
+  fi
+
+  echo "${_flags_infoValue_}"
+  unset _flags_gFI_usName_ _flags_gfI_info_ _flags_infoValue_ _flags_infoVar_ \
+      _flags_strToEval_ _flags_typeValue_ _flags_typeVar_
+  [ ${flags_return} -eq ${FLAGS_ERROR} ] && _flags_error "${flags_error}"
+  return ${flags_return}
+}
+
+# Check for presence of item in a list.
+#
+# Passed a string (e.g. 'abc'), this function will determine if the string is
+# present in the list of strings (e.g.  ' foo bar abc ').
+#
+# Args:
+#   _flags_str_: string: string to search for in a list of strings
+#   unnamed: list: list of strings
+# Returns:
+#   boolean: true if item is in the list
+_flags_itemInList() {
+  _flags_str_=$1
+  shift
+
+  case " ${*:-} " in
+    *\ ${_flags_str_}\ *) flags_return=${FLAGS_TRUE} ;;
+    *) flags_return=${FLAGS_FALSE} ;;
+  esac
+
+  unset _flags_str_
+  return ${flags_return}
+}
+
+# Returns the width of the current screen.
+#
+# Output:
+#   integer: width in columns of the current screen.
+_flags_columns() {
+  if [ -z "${__flags_columns}" ]; then
+    if eval stty size >/dev/null 2>&1; then
+      # stty size worked :-)
+      # shellcheck disable=SC2046
+      set -- `stty size`
+      __flags_columns="${2:-}"
+    fi
+  fi
+  if [ -z "${__flags_columns}" ]; then
+   if eval tput cols >/dev/null 2>&1; then
+      # shellcheck disable=SC2046
+      set -- `tput cols`
+      __flags_columns="${1:-}"
+    fi
+  fi
+  echo "${__flags_columns:-80}"
+}
+
+# Validate a boolean.
+#
+# Args:
+#   _flags__bool: boolean: value to validate
+# Returns:
+#   bool: true if the value is a valid boolean
+_flags_validBool() {
+  _flags_bool_=$1
+
+  flags_return=${FLAGS_TRUE}
+  case "${_flags_bool_}" in
+    true|t|0) ;;
+    false|f|1) ;;
+    *) flags_return=${FLAGS_FALSE} ;;
+  esac
+
+  unset _flags_bool_
+  return ${flags_return}
+}
+
+# Validate a float.
+#
+# Args:
+#   _flags_float_: float: value to validate
+# Returns:
+#   bool: true if the value is a valid integer
+_flags_validFloat() {
+  flags_return=${FLAGS_FALSE}
+  [ -n "$1" ] || return ${flags_return}
+  _flags_float_=$1
+
+  if _flags_validInt "${_flags_float_}"; then
+    flags_return=${FLAGS_TRUE}
+  elif _flags_useBuiltin; then
+    _flags_float_whole_=${_flags_float_%.*}
+    _flags_float_fraction_=${_flags_float_#*.}
+    if _flags_validInt "${_flags_float_whole_:-0}" -a \
+      _flags_validInt "${_flags_float_fraction_}"; then
+      flags_return=${FLAGS_TRUE}
+    fi
+    unset _flags_float_whole_ _flags_float_fraction_
+  else
+    flags_return=${FLAGS_TRUE}
+    case ${_flags_float_} in
+      -*)  # Negative floats.
+        _flags_test_=`${FLAGS_EXPR_CMD} "${_flags_float_}" :\
+            '\(-[0-9]*\.[0-9]*\)'`
+        ;;
+      *)  # Positive floats.
+        _flags_test_=`${FLAGS_EXPR_CMD} "${_flags_float_}" :\
+            '\([0-9]*\.[0-9]*\)'`
+        ;;
+    esac
+    [ "${_flags_test_}" != "${_flags_float_}" ] && flags_return=${FLAGS_FALSE}
+    unset _flags_test_
+  fi
+
+  unset _flags_float_ _flags_float_whole_ _flags_float_fraction_
+  return ${flags_return}
+}
+
+# Validate an integer.
+#
+# Args:
+#   _flags_int_: integer: value to validate
+# Returns:
+#   bool: true if the value is a valid integer
+_flags_validInt() {
+  flags_return=${FLAGS_FALSE}
+  [ -n "$1" ] || return ${flags_return}
+  _flags_int_=$1
+
+  case ${_flags_int_} in
+    -*.*) ;;  # Ignore negative floats (we'll invalidate them later).
+    -*)  # Strip possible leading negative sign.
+      if _flags_useBuiltin; then
+        _flags_int_=${_flags_int_#-}
+      else
+        _flags_int_=`${FLAGS_EXPR_CMD} "${_flags_int_}" : '-\([0-9][0-9]*\)'`
+      fi
+      ;;
+  esac
+
+  case ${_flags_int_} in
+    *[!0-9]*) flags_return=${FLAGS_FALSE} ;;
+    *) flags_return=${FLAGS_TRUE} ;;
+  esac
+
+  unset _flags_int_
+  return ${flags_return}
+}
+
+# Parse command-line options using the standard getopt.
+#
+# Note: the flag options are passed around in the global __flags_opts so that
+# the formatting is not lost due to shell parsing and such.
+#
+# Args:
+#   @: varies: command-line options to parse
+# Returns:
+#   integer: a FLAGS success condition
+_flags_getoptStandard() {
+  flags_return=${FLAGS_TRUE}
+  _flags_shortOpts_=`_flags_genOptStr ${__FLAGS_OPTSTR_SHORT}`
+
+  # Check for spaces in passed options.
+  for _flags_opt_ in "$@"; do
+    # Note: the silliness with the x's is purely for ksh93 on Ubuntu 6.06.
+    _flags_match_=`echo "x${_flags_opt_}x" |sed 's/ //g'`
+    if [ "${_flags_match_}" != "x${_flags_opt_}x" ]; then
+      flags_error='the available getopt does not support spaces in options'
+      flags_return=${FLAGS_ERROR}
+      break
+    fi
+  done
+
+  if [ ${flags_return} -eq ${FLAGS_TRUE} ]; then
+    __flags_opts=`getopt "${_flags_shortOpts_}" "$@" 2>&1`
+    _flags_rtrn_=$?
+    if [ ${_flags_rtrn_} -ne ${FLAGS_TRUE} ]; then
+      _flags_warn "${__flags_opts}"
+      flags_error='unable to parse provided options with getopt.'
+      flags_return=${FLAGS_ERROR}
+    fi
+  fi
+
+  unset _flags_match_ _flags_opt_ _flags_rtrn_ _flags_shortOpts_
+  return ${flags_return}
+}
+
+# Parse command-line options using the enhanced getopt.
+#
+# Note: the flag options are passed around in the global __flags_opts so that
+# the formatting is not lost due to shell parsing and such.
+#
+# Args:
+#   @: varies: command-line options to parse
+# Returns:
+#   integer: a FLAGS success condition
+_flags_getoptEnhanced() {
+  flags_return=${FLAGS_TRUE}
+  _flags_shortOpts_=`_flags_genOptStr ${__FLAGS_OPTSTR_SHORT}`
+  _flags_boolOpts_=`echo "${__flags_boolNames}" \
+      |sed 's/^ *//;s/ *$//;s/ /,/g'`
+  _flags_longOpts_=`_flags_genOptStr ${__FLAGS_OPTSTR_LONG}`
+
+  __flags_opts=`${FLAGS_GETOPT_CMD} \
+      -o "${_flags_shortOpts_}" \
+      -l "${_flags_longOpts_},${_flags_boolOpts_}" \
+      -- "$@" 2>&1`
+  _flags_rtrn_=$?
+  if [ ${_flags_rtrn_} -ne ${FLAGS_TRUE} ]; then
+    _flags_warn "${__flags_opts}"
+    flags_error='unable to parse provided options with getopt.'
+    flags_return=${FLAGS_ERROR}
+  fi
+
+  unset _flags_boolOpts_ _flags_longOpts_ _flags_rtrn_ _flags_shortOpts_
+  return ${flags_return}
+}
+
+# Dynamically parse a getopt result and set appropriate variables.
+#
+# This function does the actual conversion of getopt output and runs it through
+# the standard case structure for parsing. The case structure is actually quite
+# dynamic to support any number of flags.
+#
+# Args:
+#   argc: int: original command-line argument count
+#   @: varies: output from getopt parsing
+# Returns:
+#   integer: a FLAGS success condition
+_flags_parseGetopt() {
+  _flags_argc_=$1
+  shift
+
+  flags_return=${FLAGS_TRUE}
+
+  if [ "${__FLAGS_GETOPT_VERS}" -ne "${__FLAGS_GETOPT_VERS_ENH}" ]; then
+    # The @$ must be unquoted as it needs to be re-split.
+    #   shellcheck disable=SC2068
+    set -- $@
+  else
+    # Note the quotes around the `$@' -- they are essential!
+    eval set -- "$@"
+  fi
+
+  # Provide user with the number of arguments to shift by later.
+  # NOTE: the FLAGS_ARGC variable is obsolete as of 1.0.3 because it does not
+  # properly give user access to non-flag arguments mixed in between flag
+  # arguments. Its usage was replaced by FLAGS_ARGV, and it is being kept only
+  # for backwards compatibility reasons.
+  FLAGS_ARGC=`_flags_math "$# - 1 - ${_flags_argc_}"`
+  export FLAGS_ARGC
+
+  # Handle options. note options with values must do an additional shift.
+  while true; do
+    _flags_opt_=$1
+    _flags_arg_=${2:-}
+    _flags_type_=${__FLAGS_TYPE_NONE}
+    _flags_name_=''
+
+    # Determine long flag name.
+    case "${_flags_opt_}" in
+      --) shift; break ;;  # Discontinue option parsing.
+
+      --*)  # Long option.
+        if _flags_useBuiltin; then
+          _flags_opt_=${_flags_opt_#*--}
+        else
+          _flags_opt_=`${FLAGS_EXPR_CMD} "${_flags_opt_}" : '--\(.*\)'`
+        fi
+        _flags_len_=${__FLAGS_LEN_LONG}
+        if _flags_itemInList "${_flags_opt_}" "${__flags_longNames}"; then
+          _flags_name_=${_flags_opt_}
+        else
+          # Check for negated long boolean version.
+          if _flags_itemInList "${_flags_opt_}" "${__flags_boolNames}"; then
+            if _flags_useBuiltin; then
+              _flags_name_=${_flags_opt_#*no}
+            else
+              _flags_name_=`${FLAGS_EXPR_CMD} "${_flags_opt_}" : 'no\(.*\)'`
+            fi
+            _flags_type_=${__FLAGS_TYPE_BOOLEAN}
+            _flags_arg_=${__FLAGS_NULL}
+          fi
+        fi
+        ;;
+
+      -*)  # Short option.
+        if _flags_useBuiltin; then
+          _flags_opt_=${_flags_opt_#*-}
+        else
+          _flags_opt_=`${FLAGS_EXPR_CMD} "${_flags_opt_}" : '-\(.*\)'`
+        fi
+        _flags_len_=${__FLAGS_LEN_SHORT}
+        if _flags_itemInList "${_flags_opt_}" "${__flags_shortNames}"; then
+          # Yes. Match short name to long name. Note purposeful off-by-one
+          # (too high) with awk calculations.
+          _flags_pos_=`echo "${__flags_shortNames}" \
+              |awk 'BEGIN{RS=" ";rn=0}$0==e{rn=NR}END{print rn}' \
+                  e="${_flags_opt_}"`
+          _flags_name_=`echo "${__flags_longNames}" \
+              |awk 'BEGIN{RS=" "}rn==NR{print $0}' rn="${_flags_pos_}"`
+        fi
+        ;;
+    esac
+
+    # Die if the flag was unrecognized.
+    if [ -z "${_flags_name_}" ]; then
+      flags_error="unrecognized option (${_flags_opt_})"
+      flags_return=${FLAGS_ERROR}
+      break
+    fi
+
+    # Set new flag value.
+    _flags_usName_=`_flags_underscoreName "${_flags_name_}"`
+    [ ${_flags_type_} -eq ${__FLAGS_TYPE_NONE} ] && \
+        _flags_type_=`_flags_getFlagInfo \
+            "${_flags_usName_}" ${__FLAGS_INFO_TYPE}`
+    case ${_flags_type_} in
+      ${__FLAGS_TYPE_BOOLEAN})
+        if [ ${_flags_len_} -eq ${__FLAGS_LEN_LONG} ]; then
+          if [ "${_flags_arg_}" != "${__FLAGS_NULL}" ]; then
+            eval "FLAGS_${_flags_usName_}=${FLAGS_TRUE}"
+          else
+            eval "FLAGS_${_flags_usName_}=${FLAGS_FALSE}"
+          fi
+        else
+          _flags_strToEval_="_flags_val_=\
+\${__flags_${_flags_usName_}_${__FLAGS_INFO_DEFAULT}}"
+          eval "${_flags_strToEval_}"
+          # shellcheck disable=SC2154
+          if [ "${_flags_val_}" -eq ${FLAGS_FALSE} ]; then
+            eval "FLAGS_${_flags_usName_}=${FLAGS_TRUE}"
+          else
+            eval "FLAGS_${_flags_usName_}=${FLAGS_FALSE}"
+          fi
+        fi
+        ;;
+
+      ${__FLAGS_TYPE_FLOAT})
+        if _flags_validFloat "${_flags_arg_}"; then
+          eval "FLAGS_${_flags_usName_}='${_flags_arg_}'"
+        else
+          flags_error="invalid float value (${_flags_arg_})"
+          flags_return=${FLAGS_ERROR}
+          break
+        fi
+        ;;
+
+      ${__FLAGS_TYPE_INTEGER})
+        if _flags_validInt "${_flags_arg_}"; then
+          eval "FLAGS_${_flags_usName_}='${_flags_arg_}'"
+        else
+          flags_error="invalid integer value (${_flags_arg_})"
+          flags_return=${FLAGS_ERROR}
+          break
+        fi
+        ;;
+
+      ${__FLAGS_TYPE_STRING})
+        eval "FLAGS_${_flags_usName_}='${_flags_arg_}'"
+        ;;
+    esac
+
+    # Handle special case help flag.
+    if [ "${_flags_usName_}" = 'help' ]; then
+      # shellcheck disable=SC2154
+      if [ "${FLAGS_help}" -eq ${FLAGS_TRUE} ]; then
+        flags_help
+        flags_error='help requested'
+        flags_return=${FLAGS_FALSE}
+        break
+      fi
+    fi
+
+    # Shift the option and non-boolean arguments out.
+    shift
+    [ "${_flags_type_}" != ${__FLAGS_TYPE_BOOLEAN} ] && shift
+  done
+
+  # Give user back non-flag arguments.
+  FLAGS_ARGV=''
+  while [ $# -gt 0 ]; do
+    FLAGS_ARGV="${FLAGS_ARGV:+${FLAGS_ARGV} }'$1'"
+    shift
+  done
+
+  unset _flags_arg_ _flags_len_ _flags_name_ _flags_opt_ _flags_pos_ \
+      _flags_strToEval_ _flags_type_ _flags_usName_ _flags_val_
+  return ${flags_return}
+}
+
+# Perform some path using built-ins.
+#
+# Args:
+#   $@: string: math expression to evaluate
+# Output:
+#   integer: the result
+# Returns:
+#   bool: success of math evaluation
+_flags_math() {
+  if [ $# -eq 0 ]; then
+    flags_return=${FLAGS_FALSE}
+  elif _flags_useBuiltin; then
+    # Variable assignment is needed as workaround for Solaris Bourne shell,
+    # which cannot parse a bare $((expression)).
+    # shellcheck disable=SC2016
+    _flags_expr_='$(($@))'
+    eval echo ${_flags_expr_}
+    flags_return=$?
+    unset _flags_expr_
+  else
+    eval expr "$@"
+    flags_return=$?
+  fi
+
+  return ${flags_return}
+}
+
+# Cross-platform strlen() implementation.
+#
+# Args:
+#   _flags_str: string: to determine length of
+# Output:
+#   integer: length of string
+# Returns:
+#   bool: success of strlen evaluation
+_flags_strlen() {
+  _flags_str_=${1:-}
+
+  if [ -z "${_flags_str_}" ]; then
+    flags_output=0
+  elif _flags_useBuiltin; then
+    flags_output=${#_flags_str_}
+  else
+    flags_output=`${FLAGS_EXPR_CMD} "${_flags_str_}" : '.*'`
+  fi
+  flags_return=$?
+
+  unset _flags_str_
+  echo "${flags_output}"
+  return ${flags_return}
+}
+
+# Use built-in helper function to enable unit testing.
+#
+# Args:
+#   None
+# Returns:
+#   bool: true if built-ins should be used
+_flags_useBuiltin() { return ${__FLAGS_USE_BUILTIN}; }
+
+#------------------------------------------------------------------------------
+# public functions
+#
+# A basic boolean flag. Boolean flags do not take any arguments, and their
+# value is either 1 (false) or 0 (true). For long flags, the false value is
+# specified on the command line by prepending the word 'no'. With short flags,
+# the presence of the flag toggles the current value between true and false.
+# Specifying a short boolean flag twice on the command results in returning the
+# value back to the default value.
+#
+# A default value is required for boolean flags.
+#
+# For example, lets say a Boolean flag was created whose long name was 'update'
+# and whose short name was 'x', and the default value was 'false'. This flag
+# could be explicitly set to 'true' with '--update' or by '-x', and it could be
+# explicitly set to 'false' with '--noupdate'.
+DEFINE_boolean() { _flags_define ${__FLAGS_TYPE_BOOLEAN} "$@"; }
+
+# Other basic flags.
+DEFINE_float()   { _flags_define ${__FLAGS_TYPE_FLOAT} "$@"; }
+DEFINE_integer() { _flags_define ${__FLAGS_TYPE_INTEGER} "$@"; }
+DEFINE_string()  { _flags_define ${__FLAGS_TYPE_STRING} "$@"; }
+
+# Parse the flags.
+#
+# Args:
+#   unnamed: list: command-line flags to parse
+# Returns:
+#   integer: success of operation, or error
+FLAGS() {
+  # Define a standard 'help' flag if one isn't already defined.
+  [ -z "${__flags_help_type:-}" ] && \
+      DEFINE_boolean 'help' false 'show this help' 'h'
+
+  # Parse options.
+  if [ $# -gt 0 ]; then
+    if [ "${__FLAGS_GETOPT_VERS}" -ne "${__FLAGS_GETOPT_VERS_ENH}" ]; then
+      _flags_getoptStandard "$@"
+    else
+      _flags_getoptEnhanced "$@"
+    fi
+    flags_return=$?
+  else
+    # Nothing passed; won't bother running getopt.
+    __flags_opts='--'
+    flags_return=${FLAGS_TRUE}
+  fi
+
+  if [ ${flags_return} -eq ${FLAGS_TRUE} ]; then
+    _flags_parseGetopt $# "${__flags_opts}"
+    flags_return=$?
+  fi
+
+  [ ${flags_return} -eq ${FLAGS_ERROR} ] && _flags_fatal "${flags_error}"
+  return ${flags_return}
+}
+
+# This is a helper function for determining the 'getopt' version for platforms
+# where the detection isn't working. It simply outputs debug information that
+# can be included in a bug report.
+#
+# Args:
+#   none
+# Output:
+#   debug info that can be included in a bug report
+# Returns:
+#   nothing
+flags_getoptInfo() {
+  # Platform info.
+  _flags_debug "uname -a: `uname -a`"
+  _flags_debug "PATH: ${PATH}"
+
+  # Shell info.
+  if [ -n "${BASH_VERSION:-}" ]; then
+    _flags_debug 'shell: bash'
+    _flags_debug "BASH_VERSION: ${BASH_VERSION}"
+  elif [ -n "${ZSH_VERSION:-}" ]; then
+    _flags_debug 'shell: zsh'
+    _flags_debug "ZSH_VERSION: ${ZSH_VERSION}"
+  fi
+
+  # getopt info.
+  ${FLAGS_GETOPT_CMD} >/dev/null
+  _flags_getoptReturn=$?
+  _flags_debug "getopt return: ${_flags_getoptReturn}"
+  _flags_debug "getopt --version: `${FLAGS_GETOPT_CMD} --version 2>&1`"
+
+  unset _flags_getoptReturn
+}
+
+# Returns whether the detected getopt version is the enhanced version.
+#
+# Args:
+#   none
+# Output:
+#   none
+# Returns:
+#   bool: true if getopt is the enhanced version
+flags_getoptIsEnh() {
+  test "${__FLAGS_GETOPT_VERS}" -eq "${__FLAGS_GETOPT_VERS_ENH}"
+}
+
+# Returns whether the detected getopt version is the standard version.
+#
+# Args:
+#   none
+# Returns:
+#   bool: true if getopt is the standard version
+flags_getoptIsStd() {
+  test "${__FLAGS_GETOPT_VERS}" -eq "${__FLAGS_GETOPT_VERS_STD}"
+}
+
+# This is effectively a 'usage()' function. It prints usage information and
+# exits the program with ${FLAGS_FALSE} if it is ever found in the command line
+# arguments. Note this function can be overridden so other apps can define
+# their own --help flag, replacing this one, if they want.
+#
+# Args:
+#   none
+# Returns:
+#   integer: success of operation (always returns true)
+flags_help() {
+  if [ -n "${FLAGS_HELP:-}" ]; then
+    echo "${FLAGS_HELP}" >&2
+  else
+    echo "USAGE: ${FLAGS_PARENT:-$0} [flags] args" >&2
+  fi
+  if [ -n "${__flags_longNames}" ]; then
+    echo 'flags:' >&2
+    for flags_name_ in ${__flags_longNames}; do
+      flags_flagStr_=''
+      flags_boolStr_=''
+      flags_usName_=`_flags_underscoreName "${flags_name_}"`
+
+      flags_default_=`_flags_getFlagInfo \
+          "${flags_usName_}" ${__FLAGS_INFO_DEFAULT}`
+      flags_help_=`_flags_getFlagInfo \
+          "${flags_usName_}" ${__FLAGS_INFO_HELP}`
+      flags_short_=`_flags_getFlagInfo \
+          "${flags_usName_}" ${__FLAGS_INFO_SHORT}`
+      flags_type_=`_flags_getFlagInfo \
+          "${flags_usName_}" ${__FLAGS_INFO_TYPE}`
+
+      [ "${flags_short_}" != "${__FLAGS_NULL}" ] && \
+          flags_flagStr_="-${flags_short_}"
+
+      if [ "${__FLAGS_GETOPT_VERS}" -eq "${__FLAGS_GETOPT_VERS_ENH}" ]; then
+        [ "${flags_short_}" != "${__FLAGS_NULL}" ] && \
+            flags_flagStr_="${flags_flagStr_},"
+        # Add [no] to long boolean flag names, except the 'help' flag.
+        [ "${flags_type_}" -eq ${__FLAGS_TYPE_BOOLEAN} \
+          -a "${flags_usName_}" != 'help' ] && \
+            flags_boolStr_='[no]'
+        flags_flagStr_="${flags_flagStr_}--${flags_boolStr_}${flags_name_}:"
+      fi
+
+      case ${flags_type_} in
+        ${__FLAGS_TYPE_BOOLEAN})
+          if [ "${flags_default_}" -eq ${FLAGS_TRUE} ]; then
+            flags_defaultStr_='true'
+          else
+            flags_defaultStr_='false'
+          fi
+          ;;
+        ${__FLAGS_TYPE_FLOAT}|${__FLAGS_TYPE_INTEGER})
+          flags_defaultStr_=${flags_default_} ;;
+        ${__FLAGS_TYPE_STRING}) flags_defaultStr_="'${flags_default_}'" ;;
+      esac
+      flags_defaultStr_="(default: ${flags_defaultStr_})"
+
+      flags_helpStr_="  ${flags_flagStr_}  ${flags_help_:+${flags_help_} }${flags_defaultStr_}"
+      _flags_strlen "${flags_helpStr_}" >/dev/null
+      flags_helpStrLen_=${flags_output}
+      flags_columns_=`_flags_columns`
+
+      if [ "${flags_helpStrLen_}" -lt "${flags_columns_}" ]; then
+        echo "${flags_helpStr_}" >&2
+      else
+        echo "  ${flags_flagStr_}  ${flags_help_}" >&2
+        # Note: the silliness with the x's is purely for ksh93 on Ubuntu 6.06
+        # because it doesn't like empty strings when used in this manner.
+        flags_emptyStr_="`echo \"x${flags_flagStr_}x\" \
+            |awk '{printf "%"length($0)-2"s", ""}'`"
+        flags_helpStr_="  ${flags_emptyStr_}  ${flags_defaultStr_}"
+        _flags_strlen "${flags_helpStr_}" >/dev/null
+        flags_helpStrLen_=${flags_output}
+
+        if [ "${__FLAGS_GETOPT_VERS}" -eq "${__FLAGS_GETOPT_VERS_STD}" \
+            -o "${flags_helpStrLen_}" -lt "${flags_columns_}" ]; then
+          # Indented to match help string.
+          echo "${flags_helpStr_}" >&2
+        else
+          # Indented four from left to allow for longer defaults as long flag
+          # names might be used too, making things too long.
+          echo "    ${flags_defaultStr_}" >&2
+        fi
+      fi
+    done
+  fi
+
+  unset flags_boolStr_ flags_default_ flags_defaultStr_ flags_emptyStr_ \
+      flags_flagStr_ flags_help_ flags_helpStr flags_helpStrLen flags_name_ \
+      flags_columns_ flags_short_ flags_type_ flags_usName_
+  return ${FLAGS_TRUE}
+}
+
+# Reset shflags back to an uninitialized state.
+#
+# Args:
+#   none
+# Returns:
+#   nothing
+flags_reset() {
+  for flags_name_ in ${__flags_longNames}; do
+    flags_usName_=`_flags_underscoreName "${flags_name_}"`
+    flags_strToEval_="unset FLAGS_${flags_usName_}"
+    for flags_type_ in \
+        ${__FLAGS_INFO_DEFAULT} \
+        ${__FLAGS_INFO_HELP} \
+        ${__FLAGS_INFO_SHORT} \
+        ${__FLAGS_INFO_TYPE}
+    do
+      flags_strToEval_=\
+"${flags_strToEval_} __flags_${flags_usName_}_${flags_type_}"
+    done
+    eval "${flags_strToEval_}"
+  done
+
+  # Reset internal variables.
+  __flags_boolNames=' '
+  __flags_longNames=' '
+  __flags_shortNames=' '
+  __flags_definedNames=' '
+
+  # Reset logging level back to default.
+  flags_setLoggingLevel ${__FLAGS_LEVEL_DEFAULT}
+
+  unset flags_name_ flags_type_ flags_strToEval_ flags_usName_
+}
+
+#
+# Initialization
+#
+
+# Set the default logging level.
+flags_setLoggingLevel ${__FLAGS_LEVEL_DEFAULT}
diff --git a/test/lib/shlib b/test/lib/shlib
new file mode 100644
index 0000000..a843043
--- /dev/null
+++ b/test/lib/shlib
@@ -0,0 +1,39 @@
+# vim:et:ft=sh:sts=2:sw=2
+#
+# Copyright 2008 Kate Ward. All Rights Reserved.
+# Released under the LGPL (GNU Lesser General Public License).
+#
+# Author: kate.ward@forestent.com (Kate Ward)
+#
+# Library of shell functions.
+
+# Convert a relative path into it's absolute equivalent.
+#
+# This function will automatically prepend the current working directory if the
+# path is not already absolute. It then removes all parent references (../) to
+# reconstruct the proper absolute path.
+#
+# Args:
+#   shlib_path_: string: relative path
+# Outputs:
+#   string: absolute path
+shlib_relToAbsPath()
+{
+  shlib_path_=$1
+
+  # prepend current directory to relative paths
+  echo "${shlib_path_}" |grep '^/' >/dev/null 2>&1 \
+      || shlib_path_="${PWD}/${shlib_path_}"
+
+  # clean up the path. if all seds supported true regular expressions, then
+  # this is what it would be:
+  shlib_old_=${shlib_path_}
+  while true; do
+    shlib_new_=`echo "${shlib_old_}" |sed 's/[^/]*\/\.\.\/*//;s/\/\.\//\//'`
+    [ "${shlib_old_}" = "${shlib_new_}" ] && break
+    shlib_old_=${shlib_new_}
+  done
+  echo "${shlib_new_}"
+
+  unset shlib_path_ shlib_old_ shlib_new_
+}
diff --git a/test/lib/versions b/test/lib/versions
new file mode 100755
index 0000000..95eebd3
--- /dev/null
+++ b/test/lib/versions
@@ -0,0 +1,251 @@
+#! /bin/sh
+# vim:et:ft=sh:sts=2:sw=2
+#
+# Versions determines the versions of all installed shells.
+#
+# Copyright 2008-2017 Kate Ward. All Rights Reserved.
+# Released under the Apache 2.0 License.
+#
+# Author: kate.ward@forestent.com (Kate Ward)
+# https://github.com/kward/shlib
+#
+# This library provides reusable functions that determine actual names and
+# versions of installed shells and the OS. The library can also be run as a
+# script if set executable.
+#
+# Disable checks that aren't fully portable (POSIX != portable).
+# shellcheck disable=SC2006
+
+ARGV0=`basename "$0"`
+LSB_RELEASE='/etc/lsb-release'
+VERSIONS_SHELLS="ash /bin/bash /bin/dash /bin/ksh /bin/pdksh /bin/sh /bin/zsh"
+
+true; TRUE=$?
+false; FALSE=$?
+ERROR=2
+
+UNAME_R=`uname -r`
+UNAME_S=`uname -s`
+
+__versions_haveStrings=${ERROR}
+
+versions_osName() {
+  os_name_='unrecognized'
+  os_system_=${UNAME_S}
+  os_release_=${UNAME_R}
+  case ${os_system_} in
+    CYGWIN_NT-*) os_name_='Cygwin' ;;
+    Darwin)
+      os_name_=`/usr/bin/sw_vers -productName`
+      os_version_=`versions_osVersion`
+      case ${os_version_} in
+        10.4|10.4.[0-9]*) os_name_='Mac OS X Tiger' ;;
+        10.5|10.5.[0-9]*) os_name_='Mac OS X Leopard' ;;
+        10.6|10.6.[0-9]*) os_name_='Mac OS X Snow Leopard' ;;
+        10.7|10.7.[0-9]*) os_name_='Mac OS X Lion' ;;
+        10.8|10.8.[0-9]*) os_name_='Mac OS X Mountain Lion' ;;
+        10.9|10.9.[0-9]*) os_name_='Mac OS X Mavericks' ;;
+        10.10|10.10.[0-9]*) os_name_='Mac OS X Yosemite' ;;
+        10.11|10.11.[0-9]*) os_name_='Mac OS X El Capitan' ;;
+        10.12|10.12.[0-9]*) os_name_='macOS Sierra' ;;
+        10.13|10.13.[0-9]*) os_name_='macOS High Sierra' ;;
+        *) os_name_='macOS' ;;
+      esac
+      ;;
+    FreeBSD) os_name_='FreeBSD' ;;
+    Linux) os_name_='Linux' ;;
+    SunOS)
+      if grep 'OpenSolaris' /etc/release >/dev/null; then
+        os_name_='OpenSolaris'
+      else
+        os_name_='Solaris'
+      fi
+      ;;
+  esac
+
+  echo ${os_name_}
+  unset os_name_ os_system_ os_release_ os_version_
+}
+
+versions_osVersion() {
+  os_version_='unrecognized'
+  os_system_=${UNAME_S}
+  os_release_=${UNAME_R}
+  case ${os_system_} in
+    CYGWIN_NT-*)
+      os_version_=`expr "${os_release_}" : '\([0-9]*\.[0-9]\.[0-9]*\).*'`
+      ;;
+    Darwin)
+      os_version_=`/usr/bin/sw_vers -productVersion`
+      ;;
+    FreeBSD)
+      os_version_=`expr "${os_release_}" : '\([0-9]*\.[0-9]*\)-.*'`
+      ;;
+    Linux)
+      if [ -r '/etc/os-release' ]; then
+          os_version_=`awk -F= '$1~/PRETTY_NAME/{print $2}' /etc/os-release \
+            |sed 's/"//g'`
+      elif [ -r '/etc/redhat-release' ]; then
+        os_version_=`cat /etc/redhat-release`
+      elif [ -r '/etc/SuSE-release' ]; then
+        os_version_=`head -n 1 /etc/SuSE-release`
+      elif [ -r "${LSB_RELEASE}" ]; then
+        if grep -q 'DISTRIB_ID=Ubuntu' "${LSB_RELEASE}"; then
+          # shellcheck disable=SC2002
+          os_version_=`cat "${LSB_RELEASE}" \
+            |awk -F= '$1~/DISTRIB_DESCRIPTION/{print $2}' \
+            |sed 's/"//g;s/ /-/g'`
+        fi
+      fi
+      ;;
+    SunOS)
+      if grep 'OpenSolaris' /etc/release >/dev/null; then
+        os_version_=`grep 'OpenSolaris' /etc/release |awk '{print $2"("$3")"}'`
+      else
+        major_=`echo "${os_release_}" |sed 's/[0-9]*\.\([0-9]*\)/\1/'`
+        minor_=`grep Solaris /etc/release |sed 's/[^u]*\(u[0-9]*\).*/\1/'`
+        os_version_="${major_}${minor_}"
+      fi
+      ;;
+  esac
+
+  echo "${os_version_}"
+  unset os_name_ os_release_ os_version_ major_ minor_
+}
+
+versions_shellVersion() {
+  shell_=$1
+
+  shell_present_=${FALSE}
+  case "${shell_}" in
+    ash)
+      [ -x '/bin/busybox' ] && shell_present_=${TRUE}
+      ;;
+    *)
+      [ -x "${shell_}" ] && shell_present_=${TRUE}
+      ;;
+  esac
+  if [ ${shell_present_} -eq ${FALSE} ]; then
+    echo 'not installed'
+    return ${FALSE}
+  fi
+
+  version_=''
+  case ${shell_} in
+    */sh)
+      # TODO(kward): fix this
+      ## this could be one of any number of shells. try until one fits.
+      #version_=`versions_shell_bash ${shell_}`
+      ## dash cannot be self determined yet
+      #[ -z "${version_}" ] && version_=`versions_shell_ksh ${shell_}`
+      ## pdksh is covered in versions_shell_ksh()
+      #[ -z "${version_}" ] && version_=`versions_shell_zsh ${shell_}`
+      ;;
+    ash) version_=`versions_shell_ash "${shell_}"` ;;
+    */bash) version_=`versions_shell_bash "${shell_}"` ;;
+    */dash)
+      # simply assuming Ubuntu Linux until somebody comes up with a better
+      # test. the following test will return an empty string if dash is not
+      # installed.
+      version_=`versions_shell_dash`
+      ;;
+    */ksh) version_=`versions_shell_ksh "${shell_}"` ;;
+    */pdksh) version_=`versions_shell_pdksh "${shell_}"` ;;
+    */zsh) version_=`versions_shell_zsh "${shell_}"` ;;
+    *) version_='invalid'
+  esac
+
+  echo "${version_:-unknown}"
+  unset shell_ version_
+}
+
+# The ash shell is included in BusyBox.
+versions_shell_ash() {
+  busybox --help |head -1 |sed 's/BusyBox v\([0-9.]*\) .*/\1/'
+}
+
+versions_shell_bash() {
+  $1 --version 2>&1 |grep 'GNU bash' |sed 's/.*version \([^ ]*\).*/\1/'
+}
+
+versions_shell_dash() {
+  eval dpkg >/dev/null 2>&1
+  [ $? -eq 127 ] && return  # return if dpkg not found
+
+  dpkg -l |grep ' dash ' |awk '{print $3}'
+}
+
+versions_shell_ksh() {
+  versions_shell_=$1
+  versions_version_=''
+
+  # Try a few different ways to figure out the version.
+  if versions_version_=`${versions_shell_} --version : 2>&1`; then
+    versions_version_=`echo "${versions_version_}" \
+      |sed 's/.*\([0-9][0-9][0-9][0-9]-[0-9][0-9]-[0-9][0-9]\).*/\1/'`
+  fi
+  if [ -z "${versions_version_}" ]; then
+    _versions_have_strings
+    versions_version_=`strings "${versions_shell_}" 2>&1 \
+      |grep Version \
+      |sed 's/^.*Version \(.*\)$/\1/;s/ s+ \$$//;s/ /-/g'`
+  fi
+  if [ -z "${versions_version_}" ]; then
+    versions_version_=`versions_shell_pdksh "${versions_shell_}"`
+  fi
+
+  echo "${versions_version_}"
+  unset versions_shell_ versions_version_
+}
+
+versions_shell_pdksh() {
+  _versions_have_strings
+  strings "$1" 2>&1 \
+  |grep 'PD KSH' \
+  |sed -e 's/.*PD KSH \(.*\)/\1/;s/ /-/g'
+}
+
+versions_shell_zsh() {
+  versions_shell_=$1
+
+  # Try a few different ways to figure out the version.
+  # shellcheck disable=SC2016
+  versions_version_=`echo 'echo ${ZSH_VERSION}' |${versions_shell_}`
+
+  if [ -z "${versions_version_}" ]; then
+    versions_version_=`${versions_shell_} --version 2>&1 |awk '{print $2}'`
+  fi
+
+  echo "${versions_version_}"
+  unset versions_shell_ versions_version_
+}
+
+# Determine if the 'strings' binary installed.
+_versions_have_strings() {
+  [ ${__versions_haveStrings} -ne ${ERROR} ] && return
+  if eval strings /dev/null >/dev/null 2>&1; then
+    __versions_haveStrings=${TRUE}
+    return
+  fi
+
+  echo 'WARN: strings not installed. try installing binutils?' >&2
+  __versions_haveStrings=${FALSE}
+}
+
+versions_main() {
+  # Treat unset variables as an error.
+  set -u
+
+  os_name=`versions_osName`
+  os_version=`versions_osVersion`
+  echo "os: ${os_name} version: ${os_version}"
+
+  for shell in ${VERSIONS_SHELLS}; do
+    shell_version=`versions_shellVersion "${shell}"`
+    echo "shell: ${shell} version: ${shell_version}"
+  done
+}
+
+if [ "${ARGV0}" = 'versions' ]; then
+  versions_main "$@"
+fi
diff --git a/test/list_test.sh b/test/list_test.sh
new file mode 100755
index 0000000..ce40d55
--- /dev/null
+++ b/test/list_test.sh
@@ -0,0 +1,25 @@
+#! /bin/bash
+
+testListFromOneElement() {
+  assertEquals 1 $(list 1)
+}
+
+testListFromEmpty() {
+  assertEquals "" "$(list)"
+}
+
+testListUnlist() {
+  assertEquals "1 3 6" "$(list 1 3 6 | unlist)"
+}
+
+testList() {
+  list=$(cat <<EOF
+1
+3
+6
+EOF
+)
+  assertEquals "$list" "$(list 1 3 6)"
+}
+
+. ./shunit2-init.sh
\ No newline at end of file
diff --git a/test/map_test.sh b/test/map_test.sh
new file mode 100755
index 0000000..b34217c
--- /dev/null
+++ b/test/map_test.sh
@@ -0,0 +1,33 @@
+#!/bin/bash
+
+testMapEmptyList() {
+  assertEquals "" "$(list | map lambda x . 'echo $(($x + 1))')"
+}
+
+testMapEmptyList_ifNoArgumentsInLambda() {
+  assertEquals "" "$(list | map lambda . 'echo 3')"
+}
+
+testMapOneElementList() {
+  assertEquals "3" "$(list 2 | map lambda x . 'echo $(($x + 1))')"
+}
+
+testMapList() {
+  assertEquals "2 3 4 5 6" "$(list {1..5} | map lambda x . 'echo $(($x + 1))' | unlist)"
+}
+
+testMapList_ifNoArgumentsInLambda() {
+  assertEquals "9 9 9 9 9" "$(list {1..5} | map lambda . 'echo 9' | unlist)"
+}
+
+testMapList_ifManyArgumentsInLambda() {
+  list {1..5} | map lambda x y . 'echo $(($x + $y))' 2> /dev/null \
+    && fail "There should be syntax error, because map is an one argument operation"
+}
+
+testFlatMap() {
+    assertEquals "1 2 3 2 3 3" "$(list {1..3} | map lambda x . 'seq $x 3' | unlist)"
+    assertEquals "d e h l l l o o r w" "$(list hello world | map lambda x . 'command fold -w 1 <<< $x' | sort | unlist)"
+}
+
+. ./shunit2-init.sh
\ No newline at end of file
diff --git a/test/prepend_test.sh b/test/prepend_test.sh
new file mode 100755
index 0000000..8e9e3a0
--- /dev/null
+++ b/test/prepend_test.sh
@@ -0,0 +1,15 @@
+#! /bin/bash
+
+testPrependToEmptyList() {
+  assertEquals 4 "$(list | prepend 4)"
+}
+
+testPrependToOneElementList() {
+  assertEquals "4 1" "$(list 1 | prepend 4 | unlist)"
+}
+
+testPrependToList() {
+  assertEquals "4 1 2 3 4 5" "$(list 1 2 3 4 5 | prepend 4 | unlist)"
+}
+
+. ./shunit2-init.sh
\ No newline at end of file
diff --git a/test/shunit2 b/test/shunit2
new file mode 100755
index 0000000..bdd79e8
--- /dev/null
+++ b/test/shunit2
@@ -0,0 +1,1137 @@
+#! /bin/sh
+# vim:et:ft=sh:sts=2:sw=2
+#
+# Copyright 2008-2018 Kate Ward. All Rights Reserved.
+# Released under the Apache 2.0 license.
+#
+# shUnit2 -- Unit testing framework for Unix shell scripts.
+# https://github.com/kward/shunit2
+#
+# Author: kate.ward@forestent.com (Kate Ward)
+#
+# shUnit2 is a xUnit based unit test framework for Bourne shell scripts. It is
+# based on the popular JUnit unit testing framework for Java.
+#
+# $() are not fully portable (POSIX != portable).
+#   shellcheck disable=SC2006
+# expr may be antiquated, but it is the only solution in some cases.
+#   shellcheck disable=SC2003
+# Commands are purposely escaped so they can be mocked outside shUnit2.
+#   shellcheck disable=SC1001,SC1012
+
+# Return if shunit2 already loaded.
+\[ -n "${SHUNIT_VERSION:-}" ] && exit 0
+SHUNIT_VERSION='2.1.7'
+
+# Return values that scripts can use.
+SHUNIT_TRUE=0
+SHUNIT_FALSE=1
+SHUNIT_ERROR=2
+
+# Logging functions.
+_shunit_warn() {
+  echo "${__shunit_ansi_yellow}shunit2:WARN${__shunit_ansi_none} $*" >&2
+}
+_shunit_error() {
+  echo "${__shunit_ansi_red}shunit2:ERROR${__shunit_ansi_none} $*" >&2
+}
+_shunit_fatal() {
+  echo "${__shunit_ansi_red}shunit2:FATAL${__shunit_ansi_none} $*" >&2
+  exit ${SHUNIT_ERROR}
+}
+
+# Determine some reasonable command defaults.
+__SHUNIT_UNAME_S=`uname -s`
+case "${__SHUNIT_UNAME_S}" in
+  BSD) __SHUNIT_CMD_EXPR='gexpr' ;;
+  *) __SHUNIT_CMD_EXPR='expr' ;;
+esac
+
+__SHUNIT_CMD_ECHO_ESC='echo -e'
+# shellcheck disable=SC2039
+\[ "`echo -e test`" = '-e test' ] && __SHUNIT_CMD_ECHO_ESC='echo'
+
+# Commands a user can override if needed.
+SHUNIT_CMD_EXPR=${SHUNIT_CMD_EXPR:-${__SHUNIT_CMD_EXPR}}
+
+# Enable color output. Options are 'never', 'always', or 'auto'.
+SHUNIT_COLOR=${SHUNIT_COLOR:-auto}
+
+# Specific shell checks.
+if \[ -n "${ZSH_VERSION:-}" ]; then
+  setopt |grep "^shwordsplit$" >/dev/null
+  if \[ $? -ne ${SHUNIT_TRUE} ]; then
+    _shunit_fatal 'zsh shwordsplit option is required for proper operation'
+  fi
+  if \[ -z "${SHUNIT_PARENT:-}" ]; then
+    _shunit_fatal "zsh does not pass \$0 through properly. please declare \
+\"SHUNIT_PARENT=\$0\" before calling shUnit2"
+  fi
+fi
+
+#
+# Constants
+#
+
+__SHUNIT_MODE_SOURCED='sourced'
+__SHUNIT_MODE_STANDALONE='standalone'
+__SHUNIT_PARENT=${SHUNIT_PARENT:-$0}
+
+# ANSI colors.
+__SHUNIT_ANSI_NONE='\033[0m'
+__SHUNIT_ANSI_RED='\033[1;31m'
+__SHUNIT_ANSI_GREEN='\033[1;32m'
+__SHUNIT_ANSI_YELLOW='\033[1;33m'
+__SHUNIT_ANSI_CYAN='\033[1;36m'
+
+# Set the constants readonly.
+__shunit_constants=`set |grep '^__SHUNIT_' |cut -d= -f1`
+echo "${__shunit_constants}" |grep '^Binary file' >/dev/null && \
+    __shunit_constants=`set |grep -a '^__SHUNIT_' |cut -d= -f1`
+for __shunit_const in ${__shunit_constants}; do
+  if \[ -z "${ZSH_VERSION:-}" ]; then
+    readonly "${__shunit_const}"
+  else
+    case ${ZSH_VERSION} in
+      [123].*) readonly "${__shunit_const}" ;;
+      *) readonly -g "${__shunit_const}"  # Declare readonly constants globally.
+    esac
+  fi
+done
+unset __shunit_const __shunit_constants
+
+#
+# Internal variables.
+#
+
+# Variables.
+__shunit_lineno=''  # Line number of executed test.
+__shunit_mode=${__SHUNIT_MODE_SOURCED}  # Operating mode.
+__shunit_reportGenerated=${SHUNIT_FALSE}  # Is report generated.
+__shunit_script=''  # Filename of unittest script (standalone mode).
+__shunit_skip=${SHUNIT_FALSE}  # Is skipping enabled.
+__shunit_suite=''  # Suite of tests to execute.
+
+# ANSI colors (populated by _shunit_configureColor()).
+__shunit_ansi_none=''
+__shunit_ansi_red=''
+__shunit_ansi_green=''
+__shunit_ansi_yellow=''
+__shunit_ansi_cyan=''
+
+# Counts of tests.
+__shunit_testSuccess=${SHUNIT_TRUE}
+__shunit_testsTotal=0
+__shunit_testsPassed=0
+__shunit_testsFailed=0
+
+# Counts of asserts.
+__shunit_assertsTotal=0
+__shunit_assertsPassed=0
+__shunit_assertsFailed=0
+__shunit_assertsSkipped=0
+
+#
+# Macros.
+#
+
+# shellcheck disable=SC2016,SC2089
+_SHUNIT_LINENO_='eval __shunit_lineno=""; if \[ "${1:-}" = "--lineno" ]; then \[ -n "$2" ] && __shunit_lineno="[$2] "; shift 2; fi'
+
+#-----------------------------------------------------------------------------
+# Assertion functions.
+#
+
+# Assert that two values are equal to one another.
+#
+# Args:
+#   message: string: failure message [optional]
+#   expected: string: expected value
+#   actual: string: actual value
+# Returns:
+#   integer: success (TRUE/FALSE/ERROR constant)
+assertEquals() {
+  # shellcheck disable=SC2090
+  ${_SHUNIT_LINENO_}
+  if \[ $# -lt 2 -o $# -gt 3 ]; then
+    _shunit_error "assertEquals() requires two or three arguments; $# given"
+    _shunit_assertFail
+    return ${SHUNIT_ERROR}
+  fi
+  _shunit_shouldSkip && return ${SHUNIT_TRUE}
+
+  shunit_message_=${__shunit_lineno}
+  if \[ $# -eq 3 ]; then
+    shunit_message_="${shunit_message_}$1"
+    shift
+  fi
+  shunit_expected_=$1
+  shunit_actual_=$2
+
+  shunit_return=${SHUNIT_TRUE}
+  if \[ "${shunit_expected_}" = "${shunit_actual_}" ]; then
+    _shunit_assertPass
+  else
+    failNotEquals "${shunit_message_}" "${shunit_expected_}" "${shunit_actual_}"
+    shunit_return=${SHUNIT_FALSE}
+  fi
+
+  unset shunit_message_ shunit_expected_ shunit_actual_
+  return ${shunit_return}
+}
+# shellcheck disable=SC2016,SC2034
+_ASSERT_EQUALS_='eval assertEquals --lineno "${LINENO:-}"'
+
+# Assert that two values are not equal to one another.
+#
+# Args:
+#   message: string: failure message [optional]
+#   expected: string: expected value
+#   actual: string: actual value
+# Returns:
+#   integer: success (TRUE/FALSE/ERROR constant)
+assertNotEquals() {
+  # shellcheck disable=SC2090
+  ${_SHUNIT_LINENO_}
+  if \[ $# -lt 2 -o $# -gt 3 ]; then
+    _shunit_error "assertNotEquals() requires two or three arguments; $# given"
+    _shunit_assertFail
+    return ${SHUNIT_ERROR}
+  fi
+  _shunit_shouldSkip && return ${SHUNIT_TRUE}
+
+  shunit_message_=${__shunit_lineno}
+  if \[ $# -eq 3 ]; then
+    shunit_message_="${shunit_message_}$1"
+    shift
+  fi
+  shunit_expected_=$1
+  shunit_actual_=$2
+
+  shunit_return=${SHUNIT_TRUE}
+  if \[ "${shunit_expected_}" != "${shunit_actual_}" ]; then
+    _shunit_assertPass
+  else
+    failSame "${shunit_message_}" "$@"
+    shunit_return=${SHUNIT_FALSE}
+  fi
+
+  unset shunit_message_ shunit_expected_ shunit_actual_
+  return ${shunit_return}
+}
+# shellcheck disable=SC2016,SC2034
+_ASSERT_NOT_EQUALS_='eval assertNotEquals --lineno "${LINENO:-}"'
+
+# Assert that a value is null (i.e. an empty string)
+#
+# Args:
+#   message: string: failure message [optional]
+#   actual: string: actual value
+# Returns:
+#   integer: success (TRUE/FALSE/ERROR constant)
+assertNull() {
+  # shellcheck disable=SC2090
+  ${_SHUNIT_LINENO_}
+  if \[ $# -lt 1 -o $# -gt 2 ]; then
+    _shunit_error "assertNull() requires one or two arguments; $# given"
+    _shunit_assertFail
+    return ${SHUNIT_ERROR}
+  fi
+  _shunit_shouldSkip && return ${SHUNIT_TRUE}
+
+  shunit_message_=${__shunit_lineno}
+  if \[ $# -eq 2 ]; then
+    shunit_message_="${shunit_message_}$1"
+    shift
+  fi
+  assertTrue "${shunit_message_}" "[ -z '$1' ]"
+  shunit_return=$?
+
+  unset shunit_message_
+  return ${shunit_return}
+}
+# shellcheck disable=SC2016,SC2034
+_ASSERT_NULL_='eval assertNull --lineno "${LINENO:-}"'
+
+# Assert that a value is not null (i.e. a non-empty string)
+#
+# Args:
+#   message: string: failure message [optional]
+#   actual: string: actual value
+# Returns:
+#   integer: success (TRUE/FALSE/ERROR constant)
+assertNotNull() {
+  # shellcheck disable=SC2090
+  ${_SHUNIT_LINENO_}
+  if \[ $# -gt 2 ]; then  # allowing 0 arguments as $1 might actually be null
+    _shunit_error "assertNotNull() requires one or two arguments; $# given"
+    _shunit_assertFail
+    return ${SHUNIT_ERROR}
+  fi
+  _shunit_shouldSkip && return ${SHUNIT_TRUE}
+
+  shunit_message_=${__shunit_lineno}
+  if \[ $# -eq 2 ]; then
+    shunit_message_="${shunit_message_}$1"
+    shift
+  fi
+  shunit_actual_=`_shunit_escapeCharactersInString "${1:-}"`
+  test -n "${shunit_actual_}"
+  assertTrue "${shunit_message_}" $?
+  shunit_return=$?
+
+  unset shunit_actual_ shunit_message_
+  return ${shunit_return}
+}
+# shellcheck disable=SC2016,SC2034
+_ASSERT_NOT_NULL_='eval assertNotNull --lineno "${LINENO:-}"'
+
+# Assert that two values are the same (i.e. equal to one another).
+#
+# Args:
+#   message: string: failure message [optional]
+#   expected: string: expected value
+#   actual: string: actual value
+# Returns:
+#   integer: success (TRUE/FALSE/ERROR constant)
+assertSame() {
+  # shellcheck disable=SC2090
+  ${_SHUNIT_LINENO_}
+  if \[ $# -lt 2 -o $# -gt 3 ]; then
+    _shunit_error "assertSame() requires two or three arguments; $# given"
+    _shunit_assertFail
+    return ${SHUNIT_ERROR}
+  fi
+  _shunit_shouldSkip && return ${SHUNIT_TRUE}
+
+  shunit_message_=${__shunit_lineno}
+  if \[ $# -eq 3 ]; then
+    shunit_message_="${shunit_message_}$1"
+    shift
+  fi
+  assertEquals "${shunit_message_}" "$1" "$2"
+  shunit_return=$?
+
+  unset shunit_message_
+  return ${shunit_return}
+}
+# shellcheck disable=SC2016,SC2034
+_ASSERT_SAME_='eval assertSame --lineno "${LINENO:-}"'
+
+# Assert that two values are not the same (i.e. not equal to one another).
+#
+# Args:
+#   message: string: failure message [optional]
+#   expected: string: expected value
+#   actual: string: actual value
+# Returns:
+#   integer: success (TRUE/FALSE/ERROR constant)
+assertNotSame() {
+  # shellcheck disable=SC2090
+  ${_SHUNIT_LINENO_}
+  if \[ $# -lt 2 -o $# -gt 3 ]; then
+    _shunit_error "assertNotSame() requires two or three arguments; $# given"
+    _shunit_assertFail
+    return ${SHUNIT_ERROR}
+  fi
+  _shunit_shouldSkip && return ${SHUNIT_TRUE}
+
+  shunit_message_=${__shunit_lineno}
+  if \[ $# -eq 3 ]; then
+    shunit_message_="${shunit_message_:-}$1"
+    shift
+  fi
+  assertNotEquals "${shunit_message_}" "$1" "$2"
+  shunit_return=$?
+
+  unset shunit_message_
+  return ${shunit_return}
+}
+# shellcheck disable=SC2016,SC2034
+_ASSERT_NOT_SAME_='eval assertNotSame --lineno "${LINENO:-}"'
+
+# Assert that a value or shell test condition is true.
+#
+# In shell, a value of 0 is true and a non-zero value is false. Any integer
+# value passed can thereby be tested.
+#
+# Shell supports much more complicated tests though, and a means to support
+# them was needed. As such, this function tests that conditions are true or
+# false through evaluation rather than just looking for a true or false.
+#
+# The following test will succeed:
+#   assertTrue 0
+#   assertTrue "[ 34 -gt 23 ]"
+# The following test will fail with a message:
+#   assertTrue 123
+#   assertTrue "test failed" "[ -r '/non/existent/file' ]"
+#
+# Args:
+#   message: string: failure message [optional]
+#   condition: string: integer value or shell conditional statement
+# Returns:
+#   integer: success (TRUE/FALSE/ERROR constant)
+assertTrue() {
+  # shellcheck disable=SC2090
+  ${_SHUNIT_LINENO_}
+  if \[ $# -lt 1 -o $# -gt 2 ]; then
+    _shunit_error "assertTrue() takes one or two arguments; $# given"
+    _shunit_assertFail
+    return ${SHUNIT_ERROR}
+  fi
+  _shunit_shouldSkip && return ${SHUNIT_TRUE}
+
+  shunit_message_=${__shunit_lineno}
+  if \[ $# -eq 2 ]; then
+    shunit_message_="${shunit_message_}$1"
+    shift
+  fi
+  shunit_condition_=$1
+
+  # See if condition is an integer, i.e. a return value.
+  shunit_match_=`expr "${shunit_condition_}" : '\([0-9]*\)'`
+  shunit_return=${SHUNIT_TRUE}
+  if \[ -z "${shunit_condition_}" ]; then
+    # Null condition.
+    shunit_return=${SHUNIT_FALSE}
+  elif \[ -n "${shunit_match_}" -a "${shunit_condition_}" = "${shunit_match_}" ]
+  then
+    # Possible return value. Treating 0 as true, and non-zero as false.
+    \[ "${shunit_condition_}" -ne 0 ] && shunit_return=${SHUNIT_FALSE}
+  else
+    # Hopefully... a condition.
+    ( eval "${shunit_condition_}" ) >/dev/null 2>&1
+    \[ $? -ne 0 ] && shunit_return=${SHUNIT_FALSE}
+  fi
+
+  # Record the test.
+  if \[ ${shunit_return} -eq ${SHUNIT_TRUE} ]; then
+    _shunit_assertPass
+  else
+    _shunit_assertFail "${shunit_message_}"
+  fi
+
+  unset shunit_message_ shunit_condition_ shunit_match_
+  return ${shunit_return}
+}
+# shellcheck disable=SC2016,SC2034
+_ASSERT_TRUE_='eval assertTrue --lineno "${LINENO:-}"'
+
+# Assert that a value or shell test condition is false.
+#
+# In shell, a value of 0 is true and a non-zero value is false. Any integer
+# value passed can thereby be tested.
+#
+# Shell supports much more complicated tests though, and a means to support
+# them was needed. As such, this function tests that conditions are true or
+# false through evaluation rather than just looking for a true or false.
+#
+# The following test will succeed:
+#   assertFalse 1
+#   assertFalse "[ 'apples' = 'oranges' ]"
+# The following test will fail with a message:
+#   assertFalse 0
+#   assertFalse "test failed" "[ 1 -eq 1 -a 2 -eq 2 ]"
+#
+# Args:
+#   message: string: failure message [optional]
+#   condition: string: integer value or shell conditional statement
+# Returns:
+#   integer: success (TRUE/FALSE/ERROR constant)
+assertFalse() {
+  # shellcheck disable=SC2090
+  ${_SHUNIT_LINENO_}
+  if \[ $# -lt 1 -o $# -gt 2 ]; then
+    _shunit_error "assertFalse() quires one or two arguments; $# given"
+    _shunit_assertFail
+    return ${SHUNIT_ERROR}
+  fi
+  _shunit_shouldSkip && return ${SHUNIT_TRUE}
+
+  shunit_message_=${__shunit_lineno}
+  if \[ $# -eq 2 ]; then
+    shunit_message_="${shunit_message_}$1"
+    shift
+  fi
+  shunit_condition_=$1
+
+  # See if condition is an integer, i.e. a return value.
+  shunit_match_=`expr "${shunit_condition_}" : '\([0-9]*\)'`
+  shunit_return=${SHUNIT_TRUE}
+  if \[ -z "${shunit_condition_}" ]; then
+    # Null condition.
+    shunit_return=${SHUNIT_FALSE}
+  elif \[ -n "${shunit_match_}" -a "${shunit_condition_}" = "${shunit_match_}" ]
+  then
+    # Possible return value. Treating 0 as true, and non-zero as false.
+    \[ "${shunit_condition_}" -eq 0 ] && shunit_return=${SHUNIT_FALSE}
+  else
+    # Hopefully... a condition.
+    ( eval "${shunit_condition_}" ) >/dev/null 2>&1
+    \[ $? -eq 0 ] && shunit_return=${SHUNIT_FALSE}
+  fi
+
+  # Record the test.
+  if \[ "${shunit_return}" -eq "${SHUNIT_TRUE}" ]; then
+    _shunit_assertPass
+  else
+    _shunit_assertFail "${shunit_message_}"
+  fi
+
+  unset shunit_message_ shunit_condition_ shunit_match_
+  return "${shunit_return}"
+}
+# shellcheck disable=SC2016,SC2034
+_ASSERT_FALSE_='eval assertFalse --lineno "${LINENO:-}"'
+
+#-----------------------------------------------------------------------------
+# Failure functions.
+#
+
+# Records a test failure.
+#
+# Args:
+#   message: string: failure message [optional]
+# Returns:
+#   integer: success (TRUE/FALSE/ERROR constant)
+fail() {
+  # shellcheck disable=SC2090
+  ${_SHUNIT_LINENO_}
+  if \[ $# -gt 1 ]; then
+    _shunit_error "fail() requires zero or one arguments; $# given"
+    return ${SHUNIT_ERROR}
+  fi
+  _shunit_shouldSkip && return ${SHUNIT_TRUE}
+
+  shunit_message_=${__shunit_lineno}
+  if \[ $# -eq 1 ]; then
+    shunit_message_="${shunit_message_}$1"
+    shift
+  fi
+
+  _shunit_assertFail "${shunit_message_}"
+
+  unset shunit_message_
+  return ${SHUNIT_FALSE}
+}
+# shellcheck disable=SC2016,SC2034
+_FAIL_='eval fail --lineno "${LINENO:-}"'
+
+# Records a test failure, stating two values were not equal.
+#
+# Args:
+#   message: string: failure message [optional]
+#   expected: string: expected value
+#   actual: string: actual value
+# Returns:
+#   integer: success (TRUE/FALSE/ERROR constant)
+failNotEquals() {
+  # shellcheck disable=SC2090
+  ${_SHUNIT_LINENO_}
+  if \[ $# -lt 2 -o $# -gt 3 ]; then
+    _shunit_error "failNotEquals() requires one or two arguments; $# given"
+    return ${SHUNIT_ERROR}
+  fi
+  _shunit_shouldSkip && return ${SHUNIT_TRUE}
+
+  shunit_message_=${__shunit_lineno}
+  if \[ $# -eq 3 ]; then
+    shunit_message_="${shunit_message_}$1"
+    shift
+  fi
+  shunit_expected_=$1
+  shunit_actual_=$2
+
+  _shunit_assertFail "${shunit_message_:+${shunit_message_} }expected:<${shunit_expected_}> but was:<${shunit_actual_}>"
+
+  unset shunit_message_ shunit_expected_ shunit_actual_
+  return ${SHUNIT_FALSE}
+}
+# shellcheck disable=SC2016,SC2034
+_FAIL_NOT_EQUALS_='eval failNotEquals --lineno "${LINENO:-}"'
+
+# Records a test failure, stating two values should have been the same.
+#
+# Args:
+#   message: string: failure message [optional]
+#   expected: string: expected value
+#   actual: string: actual value
+# Returns:
+#   integer: success (TRUE/FALSE/ERROR constant)
+failSame()
+{
+  # shellcheck disable=SC2090
+  ${_SHUNIT_LINENO_}
+  if \[ $# -lt 2 -o $# -gt 3 ]; then
+    _shunit_error "failSame() requires two or three arguments; $# given"
+    return ${SHUNIT_ERROR}
+  fi
+  _shunit_shouldSkip && return ${SHUNIT_TRUE}
+
+  shunit_message_=${__shunit_lineno}
+  if \[ $# -eq 3 ]; then
+    shunit_message_="${shunit_message_}$1"
+    shift
+  fi
+
+  _shunit_assertFail "${shunit_message_:+${shunit_message_} }expected not same"
+
+  unset shunit_message_
+  return ${SHUNIT_FALSE}
+}
+# shellcheck disable=SC2016,SC2034
+_FAIL_SAME_='eval failSame --lineno "${LINENO:-}"'
+
+# Records a test failure, stating two values were not equal.
+#
+# This is functionally equivalent to calling failNotEquals().
+#
+# Args:
+#   message: string: failure message [optional]
+#   expected: string: expected value
+#   actual: string: actual value
+# Returns:
+#   integer: success (TRUE/FALSE/ERROR constant)
+failNotSame() {
+  # shellcheck disable=SC2090
+  ${_SHUNIT_LINENO_}
+  if \[ $# -lt 2 -o $# -gt 3 ]; then
+    _shunit_error "failNotEquals() requires one or two arguments; $# given"
+    return ${SHUNIT_ERROR}
+  fi
+  _shunit_shouldSkip && return ${SHUNIT_TRUE}
+
+  shunit_message_=${__shunit_lineno}
+  if \[ $# -eq 3 ]; then
+    shunit_message_="${shunit_message_}$1"
+    shift
+  fi
+  failNotEquals "${shunit_message_}" "$1" "$2"
+  shunit_return=$?
+
+  unset shunit_message_
+  return ${shunit_return}
+}
+# shellcheck disable=SC2016,SC2034
+_FAIL_NOT_SAME_='eval failNotSame --lineno "${LINENO:-}"'
+
+#-----------------------------------------------------------------------------
+# Skipping functions.
+#
+
+# Force remaining assert and fail functions to be "skipped".
+#
+# This function forces the remaining assert and fail functions to be "skipped",
+# i.e. they will have no effect. Each function skipped will be recorded so that
+# the total of asserts and fails will not be altered.
+#
+# Args:
+#   None
+startSkipping() { __shunit_skip=${SHUNIT_TRUE}; }
+
+# Resume the normal recording behavior of assert and fail calls.
+#
+# Args:
+#   None
+endSkipping() { __shunit_skip=${SHUNIT_FALSE}; }
+
+# Returns the state of assert and fail call skipping.
+#
+# Args:
+#   None
+# Returns:
+#   boolean: (TRUE/FALSE constant)
+isSkipping() { return ${__shunit_skip}; }
+
+#-----------------------------------------------------------------------------
+# Suite functions.
+#
+
+# Stub. This function should contains all unit test calls to be made.
+#
+# DEPRECATED (as of 2.1.0)
+#
+# This function can be optionally overridden by the user in their test suite.
+#
+# If this function exists, it will be called when shunit2 is sourced. If it
+# does not exist, shunit2 will search the parent script for all functions
+# beginning with the word 'test', and they will be added dynamically to the
+# test suite.
+#
+# This function should be overridden by the user in their unit test suite.
+# Note: see _shunit_mktempFunc() for actual implementation
+#
+# Args:
+#   None
+#suite() { :; }  # DO NOT UNCOMMENT THIS FUNCTION
+
+# Adds a function name to the list of tests schedule for execution.
+#
+# This function should only be called from within the suite() function.
+#
+# Args:
+#   function: string: name of a function to add to current unit test suite
+suite_addTest() {
+  shunit_func_=${1:-}
+
+  __shunit_suite="${__shunit_suite:+${__shunit_suite} }${shunit_func_}"
+  __shunit_testsTotal=`expr ${__shunit_testsTotal} + 1`
+
+  unset shunit_func_
+}
+
+# Stub. This function will be called once before any tests are run.
+#
+# Common one-time environment preparation tasks shared by all tests can be
+# defined here.
+#
+# This function should be overridden by the user in their unit test suite.
+# Note: see _shunit_mktempFunc() for actual implementation
+#
+# Args:
+#   None
+#oneTimeSetUp() { :; }  # DO NOT UNCOMMENT THIS FUNCTION
+
+# Stub. This function will be called once after all tests are finished.
+#
+# Common one-time environment cleanup tasks shared by all tests can be defined
+# here.
+#
+# This function should be overridden by the user in their unit test suite.
+# Note: see _shunit_mktempFunc() for actual implementation
+#
+# Args:
+#   None
+#oneTimeTearDown() { :; }  # DO NOT UNCOMMENT THIS FUNCTION
+
+# Stub. This function will be called before each test is run.
+#
+# Common environment preparation tasks shared by all tests can be defined here.
+#
+# This function should be overridden by the user in their unit test suite.
+# Note: see _shunit_mktempFunc() for actual implementation
+#
+# Args:
+#   None
+#setUp() { :; }  # DO NOT UNCOMMENT THIS FUNCTION
+
+# Note: see _shunit_mktempFunc() for actual implementation
+# Stub. This function will be called after each test is run.
+#
+# Common environment cleanup tasks shared by all tests can be defined here.
+#
+# This function should be overridden by the user in their unit test suite.
+# Note: see _shunit_mktempFunc() for actual implementation
+#
+# Args:
+#   None
+#tearDown() { :; }  # DO NOT UNCOMMENT THIS FUNCTION
+
+#------------------------------------------------------------------------------
+# Internal shUnit2 functions.
+#
+
+# Create a temporary directory to store various run-time files in.
+#
+# This function is a cross-platform temporary directory creation tool. Not all
+# OSes have the `mktemp` function, so one is included here.
+#
+# Args:
+#   None
+# Outputs:
+#   string: the temporary directory that was created
+_shunit_mktempDir() {
+  # Try the standard `mktemp` function.
+  ( exec mktemp -dqt shunit.XXXXXX 2>/dev/null ) && return
+
+  # The standard `mktemp` didn't work. Use our own.
+  # shellcheck disable=SC2039
+  if \[ -r '/dev/urandom' -a -x '/usr/bin/od' ]; then
+    _shunit_random_=`/usr/bin/od -vAn -N4 -tx4 </dev/urandom \
+        |sed 's/^[^0-9a-f]*//'`
+  elif \[ -n "${RANDOM:-}" ]; then
+    # $RANDOM works
+    _shunit_random_=${RANDOM}${RANDOM}${RANDOM}$$
+  else
+    # `$RANDOM` doesn't work.
+    _shunit_date_=`date '+%Y%m%d%H%M%S'`
+    _shunit_random_=`expr "${_shunit_date_}" / $$`
+  fi
+
+  _shunit_tmpDir_="${TMPDIR:-/tmp}/shunit.${_shunit_random_}"
+  ( umask 077 && \mkdir "${_shunit_tmpDir_}" ) || \
+      _shunit_fatal 'could not create temporary directory! exiting'
+
+  echo "${_shunit_tmpDir_}"
+  unset _shunit_date_ _shunit_random_ _shunit_tmpDir_
+}
+
+# This function is here to work around issues in Cygwin.
+#
+# Args:
+#   None
+_shunit_mktempFunc() {
+  for _shunit_func_ in oneTimeSetUp oneTimeTearDown setUp tearDown suite noexec
+  do
+    _shunit_file_="${__shunit_tmpDir}/${_shunit_func_}"
+    \cat <<EOF >"${_shunit_file_}"
+#! /bin/sh
+exit ${SHUNIT_TRUE}
+EOF
+    \chmod +x "${_shunit_file_}"
+  done
+
+  unset _shunit_file_
+}
+
+# Final cleanup function to leave things as we found them.
+#
+# Besides removing the temporary directory, this function is in charge of the
+# final exit code of the unit test. The exit code is based on how the script
+# was ended (e.g. normal exit, or via Ctrl-C).
+#
+# Args:
+#   name: string: name of the trap called (specified when trap defined)
+_shunit_cleanup() {
+  _shunit_name_=$1
+
+  case ${_shunit_name_} in
+    EXIT) _shunit_signal_=0 ;;
+    INT) _shunit_signal_=2 ;;
+    TERM) _shunit_signal_=15 ;;
+    *)
+      _shunit_error "unrecognized trap value (${_shunit_name_})"
+      _shunit_signal_=0
+      ;;
+  esac
+
+  # Do our work.
+  \rm -fr "${__shunit_tmpDir}"
+
+  # Exit for all non-EXIT signals.
+  if \[ "${_shunit_name_}" != 'EXIT' ]; then
+    _shunit_warn "trapped and now handling the (${_shunit_name_}) signal"
+    # Disable EXIT trap.
+    trap 0
+    # Add 128 to signal and exit.
+    exit "`expr "${_shunit_signal_}" + 128`"
+  elif \[ ${__shunit_reportGenerated} -eq ${SHUNIT_FALSE} ] ; then
+    _shunit_assertFail 'Unknown failure encountered running a test'
+    _shunit_generateReport
+    exit ${SHUNIT_ERROR}
+  fi
+
+  unset _shunit_name_ _shunit_signal_
+}
+
+# configureOutput based on user preferences, e.g. color.
+#
+# Args:
+#   color: string: color mode (one of `always`, `auto`, or `none`).
+_shunit_configureColor() {
+  _shunit_color_=${SHUNIT_FALSE}  # By default, no color.
+  case $1 in
+    'always') _shunit_color_=${SHUNIT_TRUE} ;;
+    'auto')
+      ( exec tput >/dev/null 2>&1 )  # Check for existence of tput command.
+      if [ $? -lt 127 ]; then
+        _shunit_tput_=`tput colors`
+        # shellcheck disable=SC2166,SC2181
+        [ $? -eq 0 -a "${_shunit_tput_}" -ge 16 ] && _shunit_color_=${SHUNIT_TRUE}
+      fi
+      ;;
+    'none') ;;
+    *) _shunit_fatal "unrecognized SHUNIT_COLOR option '${SHUNIT_COLOR}'" ;;
+  esac
+
+  case ${_shunit_color_} in
+    ${SHUNIT_TRUE})
+      __shunit_ansi_none=${__SHUNIT_ANSI_NONE}
+      __shunit_ansi_red=${__SHUNIT_ANSI_RED}
+      __shunit_ansi_green=${__SHUNIT_ANSI_GREEN}
+      __shunit_ansi_yellow=${__SHUNIT_ANSI_YELLOW}
+      __shunit_ansi_cyan=${__SHUNIT_ANSI_CYAN}
+      ;;
+    ${SHUNIT_FALSE})
+      __shunit_ansi_none=''
+      __shunit_ansi_red=''
+      __shunit_ansi_green=''
+      __shunit_ansi_yellow=''
+      __shunit_ansi_cyan=''
+      ;;
+  esac
+
+  unset _shunit_color_ _shunit_tput_
+}
+
+# The actual running of the tests happens here.
+#
+# Args:
+#   None
+_shunit_execSuite() {
+  for _shunit_test_ in ${__shunit_suite}; do
+    __shunit_testSuccess=${SHUNIT_TRUE}
+
+    # disable skipping
+    endSkipping
+
+    # execute the per-test setup function
+    setUp
+
+    # execute the test
+    echo "${_shunit_test_}"
+    eval "${_shunit_test_}"
+
+    # execute the per-test tear-down function
+    tearDown
+
+    # update stats
+    if \[ ${__shunit_testSuccess} -eq ${SHUNIT_TRUE} ]; then
+      __shunit_testsPassed=`expr ${__shunit_testsPassed} + 1`
+    else
+      __shunit_testsFailed=`expr ${__shunit_testsFailed} + 1`
+    fi
+  done
+
+  unset _shunit_test_
+}
+
+# Generates the user friendly report with appropriate OK/FAILED message.
+#
+# Args:
+#   None
+# Output:
+#   string: the report of successful and failed tests, as well as totals.
+_shunit_generateReport() {
+  _shunit_ok_=${SHUNIT_TRUE}
+
+  # If no exit code was provided one, determine an appropriate one.
+  \[ "${__shunit_testsFailed}" -gt 0 \
+      -o ${__shunit_testSuccess} -eq ${SHUNIT_FALSE} ] \
+          && _shunit_ok_=${SHUNIT_FALSE}
+
+  echo
+  _shunit_msg_="Ran ${__shunit_ansi_cyan}${__shunit_testsTotal}${__shunit_ansi_none}"
+  if \[ "${__shunit_testsTotal}" -eq 1 ]; then
+    ${__SHUNIT_CMD_ECHO_ESC} "${_shunit_msg_} test."
+  else
+    ${__SHUNIT_CMD_ECHO_ESC} "${_shunit_msg_} tests."
+  fi
+
+  _shunit_failures_=''
+  _shunit_skipped_=''
+  \[ ${__shunit_assertsFailed} -gt 0 ] \
+      && _shunit_failures_="failures=${__shunit_assertsFailed}"
+  \[ ${__shunit_assertsSkipped} -gt 0 ] \
+      && _shunit_skipped_="skipped=${__shunit_assertsSkipped}"
+
+  if \[ ${_shunit_ok_} -eq ${SHUNIT_TRUE} ]; then
+    _shunit_msg_="${__shunit_ansi_green}OK${__shunit_ansi_none}"
+    \[ -n "${_shunit_skipped_}" ] \
+        && _shunit_msg_="${_shunit_msg_} (${__shunit_ansi_yellow}${_shunit_skipped_}${__shunit_ansi_none})"
+  else
+    _shunit_msg_="${__shunit_ansi_red}FAILED${__shunit_ansi_none}"
+    _shunit_msg_="${_shunit_msg_} (${__shunit_ansi_red}${_shunit_failures_}${__shunit_ansi_none}"
+    \[ -n "${_shunit_skipped_}" ] \
+        && _shunit_msg_="${_shunit_msg_},${__shunit_ansi_yellow}${_shunit_skipped_}${__shunit_ansi_none}"
+    _shunit_msg_="${_shunit_msg_})"
+  fi
+
+  echo
+  ${__SHUNIT_CMD_ECHO_ESC} "${_shunit_msg_}"
+  __shunit_reportGenerated=${SHUNIT_TRUE}
+
+  unset _shunit_failures_ _shunit_msg_ _shunit_ok_ _shunit_skipped_
+}
+
+# Test for whether a function should be skipped.
+#
+# Args:
+#   None
+# Returns:
+#   boolean: whether the test should be skipped (TRUE/FALSE constant)
+_shunit_shouldSkip() {
+  \[ ${__shunit_skip} -eq ${SHUNIT_FALSE} ] && return ${SHUNIT_FALSE}
+  _shunit_assertSkip
+}
+
+# Records a successful test.
+#
+# Args:
+#   None
+_shunit_assertPass() {
+  __shunit_assertsPassed=`expr ${__shunit_assertsPassed} + 1`
+  __shunit_assertsTotal=`expr ${__shunit_assertsTotal} + 1`
+}
+
+# Records a test failure.
+#
+# Args:
+#   message: string: failure message to provide user
+_shunit_assertFail() {
+  __shunit_testSuccess=${SHUNIT_FALSE}
+  __shunit_assertsFailed=`expr "${__shunit_assertsFailed}" + 1`
+  __shunit_assertsTotal=`expr "${__shunit_assertsTotal}" + 1`
+
+  \[ $# -gt 0 ] && ${__SHUNIT_CMD_ECHO_ESC} \
+      "${__shunit_ansi_red}ASSERT:${__shunit_ansi_none}$*"
+}
+
+# Records a skipped test.
+#
+# Args:
+#   None
+_shunit_assertSkip() {
+  __shunit_assertsSkipped=`expr "${__shunit_assertsSkipped}" + 1`
+  __shunit_assertsTotal=`expr "${__shunit_assertsTotal}" + 1`
+}
+
+# Prepare a script filename for sourcing.
+#
+# Args:
+#   script: string: path to a script to source
+# Returns:
+#   string: filename prefixed with ./ (if necessary)
+_shunit_prepForSourcing() {
+  _shunit_script_=$1
+  case "${_shunit_script_}" in
+    /*|./*) echo "${_shunit_script_}" ;;
+    *) echo "./${_shunit_script_}" ;;
+  esac
+  unset _shunit_script_
+}
+
+# Escape a character in a string.
+#
+# Args:
+#   c: string: unescaped character
+#   s: string: to escape character in
+# Returns:
+#   string: with escaped character(s)
+_shunit_escapeCharInStr() {
+  \[ -n "$2" ] || return  # No point in doing work on an empty string.
+
+  # Note: using shorter variable names to prevent conflicts with
+  # _shunit_escapeCharactersInString().
+  _shunit_c_=$1
+  _shunit_s_=$2
+
+
+  # Escape the character.
+  # shellcheck disable=SC1003,SC2086
+  echo ''${_shunit_s_}'' |sed 's/\'${_shunit_c_}'/\\\'${_shunit_c_}'/g'
+
+  unset _shunit_c_ _shunit_s_
+}
+
+# Escape a character in a string.
+#
+# Args:
+#   str: string: to escape characters in
+# Returns:
+#   string: with escaped character(s)
+_shunit_escapeCharactersInString() {
+  \[ -n "$1" ] || return  # No point in doing work on an empty string.
+
+  _shunit_str_=$1
+
+  # Note: using longer variable names to prevent conflicts with
+  # _shunit_escapeCharInStr().
+  for _shunit_char_ in '"' '$' "'" '`'; do
+    _shunit_str_=`_shunit_escapeCharInStr "${_shunit_char_}" "${_shunit_str_}"`
+  done
+
+  echo "${_shunit_str_}"
+  unset _shunit_char_ _shunit_str_
+}
+
+# Extract list of functions to run tests against.
+#
+# Args:
+#   script: string: name of script to extract functions from
+# Returns:
+#   string: of function names
+_shunit_extractTestFunctions() {
+  _shunit_script_=$1
+
+  # Extract the lines with test function names, strip of anything besides the
+  # function name, and output everything on a single line.
+  _shunit_regex_='^[ 	]*(function )*test[A-Za-z0-9_]* *\(\)'
+  # shellcheck disable=SC2196
+  egrep "${_shunit_regex_}" "${_shunit_script_}" \
+  |sed 's/^[^A-Za-z0-9_]*//;s/^function //;s/\([A-Za-z0-9_]*\).*/\1/g' \
+  |xargs
+
+  unset _shunit_regex_ _shunit_script_
+}
+
+#------------------------------------------------------------------------------
+# Main.
+#
+
+# Determine the operating mode.
+if \[ $# -eq 0 ]; then
+  __shunit_script=${__SHUNIT_PARENT}
+  __shunit_mode=${__SHUNIT_MODE_SOURCED}
+else
+  __shunit_script=$1
+  \[ -r "${__shunit_script}" ] || \
+      _shunit_fatal "unable to read from ${__shunit_script}"
+  __shunit_mode=${__SHUNIT_MODE_STANDALONE}
+fi
+
+# Create a temporary storage location.
+__shunit_tmpDir=`_shunit_mktempDir`
+
+# Provide a public temporary directory for unit test scripts.
+# TODO(kward): document this.
+SHUNIT_TMPDIR="${__shunit_tmpDir}/tmp"
+\mkdir "${SHUNIT_TMPDIR}"
+
+# Setup traps to clean up after ourselves.
+trap '_shunit_cleanup EXIT' 0
+trap '_shunit_cleanup INT' 2
+trap '_shunit_cleanup TERM' 15
+
+# Create phantom functions to work around issues with Cygwin.
+_shunit_mktempFunc
+PATH="${__shunit_tmpDir}:${PATH}"
+
+# Make sure phantom functions are executable. This will bite if `/tmp` (or the
+# current `$TMPDIR`) points to a path on a partition that was mounted with the
+# 'noexec' option. The noexec command was created with `_shunit_mktempFunc()`.
+noexec 2>/dev/null || _shunit_fatal \
+    'Please declare TMPDIR with path on partition with exec permission.'
+
+# We must manually source the tests in standalone mode.
+if \[ "${__shunit_mode}" = "${__SHUNIT_MODE_STANDALONE}" ]; then
+  # shellcheck disable=SC1090
+  . "`_shunit_prepForSourcing \"${__shunit_script}\"`"
+fi
+
+# Configure default output coloring behavior.
+_shunit_configureColor "${SHUNIT_COLOR}"
+
+# Execute the oneTimeSetUp function (if it exists).
+oneTimeSetUp
+
+# Execute the suite function defined in the parent test script.
+# DEPRECATED as of 2.1.0.
+suite
+
+# If no suite function was defined, dynamically build a list of functions.
+if \[ -z "${__shunit_suite}" ]; then
+  shunit_funcs_=`_shunit_extractTestFunctions "${__shunit_script}"`
+  for shunit_func_ in ${shunit_funcs_}; do
+    suite_addTest "${shunit_func_}"
+  done
+fi
+unset shunit_func_ shunit_funcs_
+
+_shunit_execSuite
+oneTimeTearDown
+_shunit_generateReport
+
+# That's it folks.
+\[ "${__shunit_testsFailed}" -eq 0 ]
+exit $?
diff --git a/test/shunit2-init.sh b/test/shunit2-init.sh
new file mode 100644
index 0000000..68c42ca
--- /dev/null
+++ b/test/shunit2-init.sh
@@ -0,0 +1,8 @@
+#!/bin/bash
+
+oneTimeSetUp() {
+  . ../src/fun.sh
+}
+
+# Load shUnit2.
+. ./shunit2
\ No newline at end of file
diff --git a/test/tail_test.sh b/test/tail_test.sh
new file mode 100755
index 0000000..57971ad
--- /dev/null
+++ b/test/tail_test.sh
@@ -0,0 +1,15 @@
+#! /bin/bash
+
+testTailFrom10() {
+  assertEquals "2 3 4 5 6 7 8 9 10" "$(list {1..10} | tail | unlist)"
+}
+
+testTailFromOneElementList() {
+  assertEquals "" "$(list 1 | tail)"
+}
+
+testTailFromEmptyList() {
+  assertEquals "" "$(list | tail)"
+}
+
+. ./shunit2-init.sh
\ No newline at end of file
diff --git a/test/take_test.sh b/test/take_test.sh
new file mode 100755
index 0000000..efd48ef
--- /dev/null
+++ b/test/take_test.sh
@@ -0,0 +1,23 @@
+#! /bin/bash
+
+testTake9From10() {
+  assertEquals "1 2 3 4 5 6 7 8 9" "$(list {1..10} | take 9 | unlist)"
+}
+
+testTake8From10() {
+  assertEquals "1 2 3 4 5 6 7 8" "$(list {1..10} | take 8 | unlist)"
+}
+
+testTakeAll() {
+  assertEquals "1 2 3 4 5 6 7 8 9 10" "$(list {1..10} | take 10 | unlist)"
+}
+
+testTakeMoreThanAvailable() {
+  assertEquals "1 2 3 4 5 6 7 8 9 10" "$(list {1..10} | take 15 | unlist)"
+}
+
+testTakeZero() {
+  assertEquals "" "$(list {1..10} | take 0 | unlist)"
+}
+
+. ./shunit2-init.sh
\ No newline at end of file
diff --git a/test/test_runner b/test/test_runner
new file mode 100755
index 0000000..441fb4e
--- /dev/null
+++ b/test/test_runner
@@ -0,0 +1,163 @@
+#! /bin/sh
+# vim:et:ft=sh:sts=2:sw=2
+#
+# Unit test suite runner.
+#
+# Copyright 2008-2017 Kate Ward. All Rights Reserved.
+# Released under the Apache 2.0 license.
+#
+# Author: kate.ward@forestent.com (Kate Ward)
+# https://github.com/kward/shlib
+#
+# This script runs all the unit tests that can be found, and generates a nice
+# report of the tests.
+#
+### ShellCheck (http://www.shellcheck.net/)
+# Disable source following.
+#   shellcheck disable=SC1090,SC1091
+# expr may be antiquated, but it is the only solution in some cases.
+#   shellcheck disable=SC2003
+
+# Return if test_runner already loaded.
+[ -z "${RUNNER_LOADED:-}" ] || return 0
+RUNNER_LOADED=0
+
+RUNNER_ARGV0=$(basename "$0")
+RUNNER_SHELLS='/bin/bash'
+RUNNER_TEST_SUFFIX='_test.sh'
+
+runner_warn() { echo "runner:WARN $*" >&2; }
+runner_error() { echo "runner:ERROR $*" >&2; }
+runner_fatal() { echo "runner:FATAL $*" >&2; exit 1; }
+
+runner_usage() {
+  echo "usage: ${RUNNER_ARGV0} [-e key=val ...] [-s shell(s)] [-t test(s)]"
+}
+
+_runner_tests() { echo ./*${RUNNER_TEST_SUFFIX} |sed 's#./##g'; }
+_runner_testName() {
+  # shellcheck disable=SC1117
+  _runner_testName_=$(expr "${1:-}" : "\(.*\)${RUNNER_TEST_SUFFIX}")
+  if [ -n "${_runner_testName_}" ]; then
+    echo "${_runner_testName_}"
+  else
+    echo 'unknown'
+  fi
+  unset _runner_testName_
+}
+
+main() {
+  # Find and load versions library.
+  for _runner_dir_ in . ${LIB_DIR:-lib}; do
+    if [ -r "${_runner_dir_}/versions" ]; then
+      _runner_lib_dir_="${_runner_dir_}"
+      break
+    fi
+  done
+  [ -n "${_runner_lib_dir_}" ] || runner_fatal 'Unable to find versions library.'
+  . "${_runner_lib_dir_}/versions" || runner_fatal 'Unable to load versions library.'
+  unset _runner_dir_ _runner_lib_dir_
+
+  # Process command line flags.
+  env=''
+  while getopts 'e:hs:t:' opt; do
+    case ${opt} in
+      e)  # set an environment variable
+        key=$(expr "${OPTARG}" : '\([^=]*\)=')
+        val=$(expr "${OPTARG}" : '[^=]*=\(.*\)')
+        # shellcheck disable=SC2166
+        if [ -z "${key}" -o -z "${val}" ]; then
+          runner_usage
+          exit 1
+        fi
+        eval "${key}='${val}'"
+        eval "export ${key}"
+        env="${env:+${env} }${key}"
+        ;;
+      h) runner_usage; exit 0 ;;  # help output
+      s) shells=${OPTARG} ;;  # list of shells to run
+      t) tests=${OPTARG} ;;  # list of tests to run
+      *) runner_usage; exit 1 ;;
+    esac
+  done
+  shift "$(expr ${OPTIND} - 1)"
+
+  # Fill shells and/or tests.
+  shells=${shells:-${RUNNER_SHELLS}}
+  tests=${tests:-$(_runner_tests)}
+
+  # Error checking.
+  if [ -z "${tests}" ]; then
+    runner_error 'no tests found to run; exiting'
+    exit 1
+  fi
+
+  cat <<EOF
+#------------------------------------------------------------------------------
+# System data.
+#
+
+$ uname -mprsv
+$(uname -mprsv)
+
+OS Name: $(versions_osName)
+OS Version: $(versions_osVersion)
+
+### Test run info.
+shells: ${shells}
+tests: ${tests}
+EOF
+for key in ${env}; do
+  eval "echo \"${key}=\$${key}\""
+done
+
+# Run tests.
+for shell in ${shells}; do
+  echo
+
+  cat <<EOF
+
+#------------------------------------------------------------------------------
+# Running the test suite with ${shell}.
+#
+EOF
+
+    # Check for existence of shell.
+    shell_bin=${shell}
+    shell_name=''
+    shell_present=${FALSE}
+    case ${shell} in
+      ash)
+        shell_bin=$(which busybox)
+        [ $? -eq "${TRUE}" ] && shell_present="${TRUE}"
+        shell_bin="${shell_bin} ash"
+        shell_name=${shell}
+        ;;
+      *)
+        [ -x "${shell_bin}" ] && shell_present="${TRUE}"
+        shell_name=$(basename "${shell}")
+        ;;
+    esac
+    if [ "${shell_present}" -eq "${FALSE}" ]; then
+      runner_warn "unable to run tests with the ${shell_name} shell"
+      continue
+    fi
+
+    shell_version=$(versions_shellVersion "${shell}")
+
+    echo "shell name: ${shell_name}"
+    echo "shell version: ${shell_version}"
+
+    # Execute the tests.
+    for t in ${tests}; do
+      echo
+      echo "--- Executing the '$(_runner_testName "${t}'")' test suite. ---"
+      # ${shell_bin} needs word splitting.
+      #   shellcheck disable=SC2086
+      ( exec ${shell_bin} "./${t}" 2>&1; )
+    done
+  done
+}
+
+# Execute main() if this is run in standalone mode (i.e. not from a unit test).
+[ -z "${SHUNIT_VERSION}" ] && main "$@"
diff --git a/test/try_test.sh b/test/try_test.sh
new file mode 100755
index 0000000..be1aeb3
--- /dev/null
+++ b/test/try_test.sh
@@ -0,0 +1,11 @@
+#! /bin/bash
+
+testTry() {
+  assertEquals 1 "$(echo 'expr 2 / 2' | try lambda _ . 'ret 0')"
+  assertEquals 0 "$(echo 'expr 2 / 0' | try lambda _ . 'ret 0')"
+  assertEquals 2 "$(echo 'expr 2 / 0' | try lambda status . 'ret $status')"
+  assertEquals 'already up to date' "$(echo 'echo already up to date' | try lambda _ . 'ret error')"
+  assertEquals 'error exit 1' "$(try λ  _ . 'echo "error"; echo exit 1' < <(echo fgit pull) | unlist)"
+}
+
+. ./shunit2-init.sh
\ No newline at end of file
diff --git a/test/tup_test.sh b/test/tup_test.sh
new file mode 100755
index 0000000..bdd5ac1
--- /dev/null
+++ b/test/tup_test.sh
@@ -0,0 +1,69 @@
+#! /bin/bash
+
+testTupIfEmpty() {
+  assertEquals '()' $(tup '')
+}
+
+testTupIfOneElement() {
+  assertEquals '(1)' $(tup 1)
+  assertEquals '(")' $(tup '"')
+  assertEquals "(')" $(tup "'")
+  assertEquals "(u002c)" $(tup ",")
+  assertEquals "(()" $(tup "(")
+  assertEquals "())" $(tup ")")
+}
+
+testTupHappyPath() {
+  assertEquals '(1,2,3,4,5)' $(tup 1 2 3 4 5)
+  assertEquals '(a-1,b-2,c-3)' $(tup 'a-1' 'b-2' 'c-3')
+  assertEquals '(a b,c d e,f)' "$(tup 'a b' 'c d e' 'f')"
+}
+
+testTupxHappyPath() {
+  assertEquals '4' $(tup 4 5 1 4 | tupx 1)
+  assertEquals '5' $(tup 4 5 1 4 | tupx 2)
+  assertEquals '1' $(tup 4 5 1 4 | tupx 3)
+  assertEquals '4' $(tup 4 5 1 4 | tupx 4)
+
+}
+
+testTupxIfEmpty() {
+  assertEquals '' "$(tup '' | tupx 1)"
+  assertEquals '' "$(tup '' | tupx 5)"
+}
+
+testTupxIfZeroIndex() {
+  assertEquals '' "$(tup 1 3 | tupx 0 2>/dev/null)"
+}
+
+testTupxIfSpecialChars() {
+  assertEquals ',' "$(tup ',' | tupx 1)"
+  assertEquals '(' "$(tup '(' | tupx 1)"
+  assertEquals ')' "$(tup ')' | tupx 1)"
+  assertEquals '()' "$(tup '()' | tupx 1)"
+  assertEquals '(' "$(tup '(' ')' | tupx 1)"
+  assertEquals '(' "$(tup '(' '(' | tupx 1)"
+  assertEquals ')' "$(tup ')' ')' | tupx 1)"
+  assertEquals ',' "$(tup 'u002c' | tupx 1)"
+}
+
+testTupxRange() {
+  assertEquals '4 5' "$(tup 4 5 1 4 | tupx 1-2 | unlist)"
+  assertEquals '4 4' "$(tup 4 5 1 4 | tupx 1,4 | unlist)"
+  assertEquals '4 5 4' "$(tup 4 5 1 4 | tupx 1,2,4 | unlist)"
+}
+
+testTupl() {
+  assertEquals '4' "$(tup 4 5 | tupl)"
+  assertEquals '4' "$(tup 4 5 6 | tupl)"
+  assertEquals '6' "$(tup 6 | tupl)"
+  assertEquals 'foo bar' "$(tup 'foo bar' 1 'one' 2 | tupl)"
+}
+
+testTupr() {
+  assertEquals '5' "$(tup 4 5 | tupr)"
+  assertEquals '5' "$(tup 1 4 5 | tupr)"
+  assertEquals '5' "$(tup 5 | tupr)"
+}
+
+. ./shunit2-init.sh
\ No newline at end of file
diff --git a/test/unlist_test.sh b/test/unlist_test.sh
new file mode 100755
index 0000000..235f344
--- /dev/null
+++ b/test/unlist_test.sh
@@ -0,0 +1,21 @@
+#! /bin/bash
+
+testUnlistFromList() {
+  list=$(cat <<EOF
+1
+2
+6
+EOF
+)
+  assertEquals "1 2 6" "$(echo $list | unlist)"
+}
+
+testUnlistFromEmptyList() {
+  assertEquals "" "$(echo | unlist)"
+}
+
+testUnlistFromOneElementList() {
+  assertEquals "1" "$(echo 1 | unlist)"
+}
+
+. ./shunit2-init.sh
\ No newline at end of file