[Haskell-beginners] Guards as extensions of patterns

[Brandon S Allbery KF8NH]

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On 9/29/10 23:17 , Russ Abbott wrote:
> I never realized that a guard can be used as an extension of a pattern.  Is
> this recommended coding? elem n xs asks whether n is an element of xs

Yep (although perhaps not ideal in this particular case).  Moreover, the
same things work in case statements (which function definition by patterns
desugar to); IIRC "if c then t else e" is internally converted to "case ()
of () | c -> t | _ -> e".

- -- 
brandon s. allbery     [linux,solaris,freebsd,perl]      allbery at kf8nh.com
system administrator  [openafs,heimdal,too many hats]  allbery at ece.cmu.edu
electrical and computer engineering, carnegie mellon university      KF8NH
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