From 03418caa85c2c56c0750e5d097f39be241faf5dd Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?S=C5=82awomir=20=C5=9Aled=C5=BA?= <slawomir.sledz@gmail.com>
Date: Sun, 18 Mar 2018 12:01:29 +0100
Subject: [PATCH] Three new functions: pass, dropw, peek

---
 src/fun.sh | 20 ++++++++++++++++++++
 1 file changed, 20 insertions(+)

diff --git a/src/fun.sh b/src/fun.sh
index 9608852..d0b3af8 100755
--- a/src/fun.sh
+++ b/src/fun.sh
@@ -193,6 +193,26 @@ filter() {
   done
 }
 
+pass() {
+  echo > /dev/null
+}
+
+dropw() {
+  local x
+  while read x && $(echo "$x" | "$@"); do
+    pass
+  done
+  [[ ! -z $x ]] && { echo $x; cat -; }
+}
+
+peek() {
+  local x
+  while read x; do
+    ([ $# -eq 0 ] && 1>&2 echo $x || 1>&2 "$@" < <(echo $x))
+    echo $x
+  done
+}
+
 stripl() {
   local arg=$1
   cat - | map lambda l . 'ret ${l##'$arg'}'