This is a good opportunity to use case syntax. You can also case on tuples, like this: ``` foo a b = case (a,b) of (A1,B1) -> fun1 (A1,B2) -> fun2 (A1,B3) -> fun3 (A1,_) -> fun4 <- this is probably not necessary anymore, unless you expect Rule2 to get more constructors. (A2,B1) -> fun5 ... ``` On Thu, May 16, 2019 at 10:14 PM Magicloud Magiclouds < magicloud.magiclouds@gmail.com> wrote:
Hi, I have trouble describing this clearly. Let me show code directly.
data Rule1 = A1 | A2 | A3 data Rule2 = B1 | B2 | B3
foo a b = if a == A1 then if b == B1 then fun1 else if b == B2 then fun2 else if b == B3 then fun3 else fun4 ...
Basically, Rule1 and Rule2 compose a matrix, for each case of Rule1 and Rule2, I need to do different things. Above is already long and not quite clear, and it is far from complete.
So my question is, is there a way/lib that I can make this clear to read/understand? _______________________________________________ Haskell-Cafe mailing list To (un)subscribe, modify options or view archives go to: http://mail.haskell.org/cgi-bin/mailman/listinfo/haskell-cafe Only members subscribed via the mailman list are allowed to post.
-- Nathan Bloomfield Code Wrangler, Team Absinthe Automattic, Inc.