On 2008 Aug 28, at 2:41, Don Stewart wrote:
ketil:
The great thing about Maybe is that once I've checked it isn't Nothing, I can extract the value and dispense with further checks.
foo mbx = maybe default (bar x) mbx
And GHC will warn me when I forget to check all cases, and prevent me from compiling at all, if I don't do any check.
...unless you use fromJust. GNU ld supports "pragmas" which cause the use of certain functions to output warnings at link time (try compiling a C program that uses gets()). It occurs to me that this, either in compiler or linker, would be a nice thing for ghc to do when using fromJust or other partial functions. -- brandon s. allbery [solaris,freebsd,perl,pugs,haskell] allbery@kf8nh.com system administrator [openafs,heimdal,too many hats] allbery@ece.cmu.edu electrical and computer engineering, carnegie mellon university KF8NH