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Type error when parameters don't match expected length could be more clear #115

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@brekk

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@brekk

Sometimes when I'm iterating I make stupid mistakes like this:

tooFew :: Integer -> Integer -> Integer
tooFew = (a, b, c, d, e) => a + b * c + d * e

tooMany :: Integer -> Integer -> Integer
tooMany = (a) => a * a

main = () => {
  tooFew(1,2,3)
  tooMany(1,2)
}

This results in these errors:

[error]: Type error
     ╭──▶ ~/madness/stranger/src/Temp.mad@1:1-2:46
     │
   1 │ ╭┤ tooFew :: Integer -> Integer -> Integer
   2 │ ├┤ tooFew = (a, b, c, d, e) => a + b * c + d * e
     • │
     • ╰╸ expected:
     •      Integer -> Integer -> Integer
     •
     •    but found:
     •      Integer
     •      -> Integer
     •      -> (Integer -> Integer -> Integer -> Integer)
     •
─────╯

[error]: Type error
     ╭──▶ ~/madness/stranger/src/Temp.mad@4:1-5:23
     │
   4 │ ╭┤ tooMany :: Integer -> Integer -> Integer
   5 │ ├┤ tooMany = (a) => a * a
     • │
     • ╰╸ expected:
     •      Integer -> (Integer -> Integer)
     •
     •    but found:
     •      Integer -> Integer
     •
─────╯

[error]: Type error
     ╭──▶ ~/madness/stranger/src/Temp.mad@8:14-8:15
     │
   8 │   tooFew(1,2,3)
     •              ┬
     •              ╰╸ expected:
     •                   Integer
     •
     •                 but found:
     •                   a -> b
     •
─────╯

Ideally if there were a hint to indicate that the listed number of parameters doesn't match the signature I'd have a better understanding of what these errors mean — I understand it now but when I made the mistake earlier I didn't understand what the types in parentheses indicated

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