The [1..] generates [1,1+1,1+1+1,1+1+1+1, ...] Those thunks all go into the heap. Then last grabs the last one and evaluates it, so they all go on the stack. Result death.
The Int instance for Enum is a bit naughty in GHC: it is strict. That is [bottom..] is bottom rather than being [bottom,bottom,bottom...]. (Actually the Report is vague on this point; sigh.) So the Int instance evaluates as it goes, while the Integer instance does not. Maybe we should make the Integer instance strict too. Simon | -----Original Message----- | From: Ian Lynagh [mailto:[EMAIL PROTECTED]] | Sent: 02 November 2001 14:32 | To: [EMAIL PROTECTED] | Subject: Stack overflow | | | | With | | main = putStrLn $ show $ last $ zip [1..] (replicate 100000 'a') | | I get | | Stack space overflow: current size 1048576 bytes. | Use `+RTS -Ksize' to increase it. | | If I Change the [1..] to ([1..] :: [Int]) then it works fine. | | | Ian | | | _______________________________________________ | Glasgow-haskell-bugs mailing list | [EMAIL PROTECTED] | http://www.haskell.org/mailman/listinfo/glasgow-| haskell-bugs | _______________________________________________ Glasgow-haskell-bugs mailing list [EMAIL PROTECTED] http://www.haskell.org/mailman/listinfo/glasgow-haskell-bugs
