On 10/15/08 23:50, Larry Evans wrote:
On 10/15/08 16:05, Larry Evans wrote:
I'd like to have an Array indices values (see http://haskell.org/onlinereport/array.html) defined on [minBound::indices ... maxBound::indices]. [snip] The aforementioned array.html has:
_ -> error "Array.!: \ \multiply defined array element")
suggesting it should detect redefinitions;
Is this a bug in my ghc library? According to:
http://www.haskell.org/ghc/docs/6.6-latest/html/libraries/base/Data-Array.ht... it's not. It's just implemented differently by libraries:
The Haskell 98 Report further specifies that if any two associations in the list have the same index, the value at that index is undefined (i.e. bottom). However in GHC's implementation, the value at such an index is the value part of the last association with that index in the list. So, if I want multiple definitions diagnosed as an error, I'll have to do it myself :(