Argument type mismatch

call.typeMismatch

Message

Type mismatch for '<name>' argument K: expected <T>, got <U>.

What it means

A literal argument's type does not match the parameter type the function's signature declares.

Why it happens

(: not (-> Bool Bool)) declares a Bool parameter, but (not 1) passes a Number literal.

How to fix it

Pass a value of the declared type, or widen the signature (e.g. to Atom) if the function is polymorphic.

(: not (-> Bool Bool))
(not 1)        ; call.typeMismatch: expected Bool, got Number

Controlled by the metta.diagnostics.typeMismatch setting.