On Sun, 05 Aug 2012 03:21:39 +0200, Matthew
I've got a function which takes in two chars, describing a playing card and a suit. An example would be 4C or TH for a 4 of Clubs or a Ten of Hearts. I need to be able to compare the ranks of a card (e.g. a King is 13), so a Card is a tuple of rank and suit. The function which parses a Card is type String -> Maybe Card.
I'm writing unit tests for this using HUnit, and ideally I'd go with a table-driven[1] approach, where each test case is a tuple of the input and the expected output. (Possibly I could expand this to a triple, or simply a list, to allow for an error message for each test case.) Then all the test function has to do is run through each case and assert as necessary. Example: [("TH", Just (Hearts, 10)), ("XH", Nothing)].
A simple solution:
parseCard :: String -> Maybe Card parseCard string = <your function to test> test :: Bool test = all testEqual [("TH", Just (Hearts, 10)), ("XH", Nothing)] where testEqual (input, output) = parseCard input == output
For a description of 'all', see: http://hackage.haskell.org/packages/archive/base/latest/doc/html/Prelude.htm... Regards, Henk-Jan van Tuyl -- http://Van.Tuyl.eu/ http://members.chello.nl/hjgtuyl/tourdemonad.html Haskell programming --