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# Error code E0805

An attribute was given an invalid number of arguments

Erroneous code example:

    #![allow(unused)]
    fn main() {
    #[inline()] // error! should either have a single argument, or no parentheses
    fn foo() {}

    #[inline(always, never)] // error! should have only one argument, not two
    fn bar() {}
    }

To fix this, either give the right number of arguments the attribute needs. In the case of inline, this could be none at all:

    #![allow(unused)]
    fn main() {
    #[inline]
    fn foo() {}
    }

or only one:

    #![allow(unused)]
    fn main() {
    #[inline(always)]
    fn foo() {}
    }