ArgListLengthsDiffer Error

Example

Differing number of arguments for each foo declaration:

foo 0 y = 0
foo x y z = x * y * z

Forgotten parenthesis around ADT deconstruction:

data Some = Three Int Int Int
          | NoneHere
           
bar Three x y z = x * y * z -- needs parenthesis around
bar NoneHere = 0

-- corrected with parenthesis
bar (Three x y z) = x * y * z
bar NoneHere = 0

Cause

ArgListLengthsDiffer arrises from a function having different numbers of argument variables.

Commonly seen when parenthesis are forgotten around an ADT deconstruction argument.

Fix

Ensure that there are the same number of arguments for each pattern matching function declaration.

Check to ensure that there are parenthesis around ADT deconstruction.

Notes

• Additional notes.