Error code E0057

An invalid number of arguments was given when calling a closure.

Erroneous code example:

let f = |x| x * 3;
let a = f();        // invalid, too few parameters
let b = f(4);       // this works!
let c = f(2, 3);    // invalid, too many parameters

When invoking closures or other implementations of the function traits Fn, FnMut or FnOnce using call notation, the number of parameters passed to the function must match its definition.

A generic function must be treated similarly:

fn foo<F: Fn()>(f: F) {
    f(); // this is valid, but f(3) would not work
}

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