
6 Sep
2006
6 Sep
'06
4:23 p.m.
David Roundy wrote:
On Wed, Sep 06, 2006 at 09:56:17AM -0700, Jason Dagit wrote:
Or maybe even more extreme you could use template haskell or the c preprocessor to fill in the line number + column.
Which is precisely what darcs does for fromJust (which we use a lot): we define a C preprocessor macro fromJust. It's ugly, but beats any other choice I'm aware of. I wish that built in functions that call error could be automatically this way...
This old mailing list message may help: http://www.mail-archive.com/haskell-cafe@haskell.org/msg13034.html
Suggested by a question from sethk on #haskell irc channel. Solves an FAQ where people have often resorted to cpp or m4: a `trace' that prints line numbers.
-- Chris