[xmonad] Issue 507 in xmonad: Pattern match failure in do expression at XMonad/Prompt.hs:601:3-14

codesite-noreply at google.com codesite-noreply at google.com
Mon Jul 23 03:29:39 CEST 2012

Comment #3 on issue 507 by manpac... at gmail.com: Pattern match failure in do  
expression at XMonad/Prompt.hs:601:3-14

Right, the problem is that lookupString already returns keypresses which  
are already in proper  unicode and whoever implemented utf8-string library  
decided not to use any checks if string is in unicode format already and  
some other guy  who implemented  Xmonad.Prompt decided that he can assume  
that color passed into initColor will be always correct and yet one more  
guy decided that catching any exceptions inside that initColor function and  
returning Nothing should be  safe - because of all this (and some haskell  
lazyness) we have a nice,  clean and 100% unrelated error message about  
this pattern match.

So if you are affected by that bug and looking for a quick fix - just go  
into XMonad.Prompt module, look for keyPressHandle function, look for  
decodeString near insertString call and just remove that decodeString part.

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