#69: Pattern match error can be arbitrarily long ---------------------+------------------------------------------------------ Reporter: neil | Owner: nobody Type: defect | Status: new Priority: major | Milestone: Component: hugs | Version: 200609 Resolution: | Keywords: ---------------------+------------------------------------------------------ Old description:

Given the program:

test n = length val `seq` f val where val = replicate n (toEnum 12)

f "" = ""

...

test 3 Program error: pattern match failure: f [toEnum 12,toEnum 12,toEnum 12]

Unfortunately, as you bump up n (try 10,000) Hugs spits and more and more information - when the most important bit of this message is "f" - which you end up loosing.

I suggest truncating pattern match errors at (say) 500 characters, or perhaps 500 characters per argument.

New description: Given the program: {{{ test n = length val `seq` f val where val = replicate n (toEnum 12) f "" = ""

test 3 Program error: pattern match failure: f [toEnum 12,toEnum 12,toEnum 12] }}}

Unfortunately, as you bump up n (try 10,000) Hugs spits and more and more information - when the most important bit of this message is "f" - which you end up loosing. I suggest truncating pattern match errors at (say) 500 characters, or perhaps 500 characters per argument. -- Ticket URL: <http://hackage.haskell.org/trac/hugs/ticket/69> Hugs <http://www.haskell.org/hugs/> Hugs 98, an interpreter for Haskell