Proposal: rename Data.Map.fromAscList to Data.Map.unsafeFromAscList

Chris Eidhof chris at
Fri Apr 24 07:58:49 EDT 2009

Hey all,

I had some code where the function elems said a certain key was  
present, but looking it up returned a Nothing. After some debugging I  
found out that it did work if I used Prelude's lookup in combination  
with toList. After even more debugging it turned out there was a  
fromAscList somewhere deep down in my code where it should have been a  

Now, I know that I shouldn't have used fromAscList and that it was  
totally my fault. I also realize this is something that can't easily  
be checked using the type system, so I propose we do the next best  
thing: prefix the name with 'unsafe'.


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