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  • #8325

Closed
Open
Opened Sep 18, 2013 by mcollis@trac-mcollis

Pattern guards in anonymous functions

In the course of a project, I had an idea that would allow less cumbersome use of cases in anonymous functions. Here's a simple example of what I'm proposing:

(\x y | x > y -> x
      | otherwise -> something else)

Currently, the only way to accomplish this is with if() then ... else syntax or the use of the MultiWayIf and LambdaCase extensions. The syntax I've proposed here matches with existing anonymous function syntax and doesn't conflict with any other GHC syntax. This would greatly improve the readability of complex anonymous functions.

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Version 7.6.3
Type FeatureRequest
TypeOfFailure OtherFailure
Priority normal
Resolution Unresolved
Component Compiler
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Reference: ghc/ghc#8325