2020-05-15 13:41:26 +03:00
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---
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layout: developer-doc
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title: Bindings
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category: semantics
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tags: [semantics, bindings]
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order: 1
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---
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# Bindings
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2020-07-21 15:59:40 +03:00
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A "binding" is a portion of and Enso program that creates a new name and binds a
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value to that name.
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2020-05-15 13:41:26 +03:00
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<!-- MarkdownTOC levels="2,3" autolink="true" -->
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- [Binding Return Value](#binding-return-value)
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<!-- /MarkdownTOC -->
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## Binding Return Value
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2020-07-21 15:59:40 +03:00
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2020-05-15 13:41:26 +03:00
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While some expression-based languages with bindings have the binding return the
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value assigned to the binding, we feel that this is far too error prone.
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Consider the following code as a demonstration:
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```ruby
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if x = someExprEvaluatingToBool then foo else bar
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```
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This is the perennially-discussed C++ bug where you fail to type `==` in an
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if-statement.
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Enso, instead, takes the approach where a binding expression returns the
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singleton value of the type `Nothing`, making the above-written code a type
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error.
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