Difference between revisions of "Talk:If-then-else"

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(liftM3 if' considered harmful)
 
(bool-extras package on Hackage)
 
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liftM3 if' (return False) deleteHardDrive (return ())
 
liftM3 if' (return False) deleteHardDrive (return ())
   
executes deleteHardDrive, then decides to return the value of (return ()).
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executes deleteHardDrive, then decides to return the value of (return ()). --[[User:ConorMcBride|Conor McBride]] 14:41, 4 March 2008 (UTC)
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== bool-extras ==
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I've just uploaded a package to Hackage that contains a similar function to the proposed <hask>if'</hask>.
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It's called <hask>bool</hask> after the data type, similarly to <hask>maybe</hask> and <hask>either</hask>. Its arguments are in the exact opposite order of the <hask>if'</hask> function, since I think this makes partial application easier (everywhere I've used it, I either provide the first or the first two arguments).
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http://hackage.haskell.org/cgi-bin/hackage-scripts/package/bool-extras
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--[[User:TomLokhorst|TomLokhorst]] 09:09, 13 May 2009 (UTC)

Latest revision as of 09:09, 13 May 2009

Just to remark that

 liftM3 if' (return False) deleteHardDrive (return ())

executes deleteHardDrive, then decides to return the value of (return ()). --Conor McBride 14:41, 4 March 2008 (UTC)

bool-extras

I've just uploaded a package to Hackage that contains a similar function to the proposed if'.

It's called bool after the data type, similarly to maybe and either. Its arguments are in the exact opposite order of the if' function, since I think this makes partial application easier (everywhere I've used it, I either provide the first or the first two arguments).

http://hackage.haskell.org/cgi-bin/hackage-scripts/package/bool-extras --TomLokhorst 09:09, 13 May 2009 (UTC)