[Haskell-cafe] Prelude.undefined

Tom Hawkins tomahawkins at gmail.com
Wed Mar 3 00:16:02 EST 2010

On Wed, Mar 3, 2010 at 6:11 AM, Tom Hawkins <tomahawkins at gmail.com> wrote:
> On Wed, Mar 3, 2010 at 6:07 AM, Ivan Miljenovic
> <ivan.miljenovic at gmail.com> wrote:
>> On 3 March 2010 16:06, Tom Hawkins <tomahawkins at gmail.com> wrote:
>>> How do I track down an reference to an undefined value?  My program
>>> must not be using a library correctly because the program makes no
>>> direct use of 'undefined'.  Running with +RTS -xc yields:
>>> <GHC.Err.CAF>Test: Prelude.undefined
>> Are you matching all patterns?  When compiling with -Wall does it make
>> any complaints?
> -Wall only complains about shadow bindings, defined but not used, and
> no type signature.  But no unmatched patterns.

BTW, I'm using:

GHC 6.12.1

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