Error explanations

[aboeglin]

Error explanation definition

Function calls

Also, after the last paragraph we should indicate how to add a typing to the signature.

Type error in function call at line 3:
fn(2, "3", "3")
           ^^^
The 3rd argument of the function "fn" has type
	String
But it was expected to be
	Num
To help you out, in this context the function fn has type:
    Num -> a -> Num -> Bool

If the function is polymorphic it is possible that the error comes from the application of other arguments.
Otherwise you might want to add a typing to the signature to improve documentation and make error messages
more precise !