Created
September 24, 2011 04:30
-
-
Save mwotton/1238970 to your computer and use it in GitHub Desktop.
yesod util function
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
orFail action = do res <- action | |
case res of | |
Just j -> return j | |
Nothing -> invalidArgs ["something went wrong"] |
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment