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42 lines
1.4 KiB
Markdown
42 lines
1.4 KiB
Markdown
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---
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title: compare.Conditional
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description: Returns one of two arguments depending on the value of the control argument.
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categories: []
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keywords: []
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action:
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aliases: [cond]
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related:
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- functions/compare/Default
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returnType: any
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signatures: [compare.Conditional CONTROL ARG1 ARG2]
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aliases: [/functions/cond]
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---
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The CONTROL argument is a boolean value that indicates whether the function should return ARG1 or ARG2. If CONTROL is `true`, the function returns ARG1. Otherwise, the function returns ARG2.
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```go-html-template
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{{ $qty := 42 }}
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{{ cond (le $qty 3) "few" "many" }} → many
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```
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The CONTROL argument must be either `true` or `false`. To cast a non-boolean value to boolean, pass it through the `not` operator twice.
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```go-html-template
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{{ cond (42 | not | not) "truthy" "falsy" }} → truthy
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{{ cond ("" | not | not) "truthy" "falsy" }} → falsy
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```
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{{% note %}}
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Unlike [ternary operators] in other languages, the `cond` function does not perform [short-circuit evaluation]. The function evaluates both ARG1 and ARG2, regardless of the CONTROL value.
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[short-circuit evaluation]: https://en.wikipedia.org/wiki/Short-circuit_evaluation
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[ternary operators]: https://en.wikipedia.org/wiki/Ternary_conditional_operator
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{{% /note %}}
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Due to the absence of short-circuit evaluation, these examples throw an error:
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```go-html-template
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{{ cond true "true" (div 1 0) }}
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{{ cond false (div 1 0) "false" }}
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```
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