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# Error code E0054

It is not allowed to cast to a bool.

Erroneous code example:

    #![allow(unused)]
    fn main() {
    let x = 5;

    // Not allowed, won't compile
    let x_is_nonzero = x as bool;
    }

If you are trying to cast a numeric type to a bool, you can compare it with zero instead:

    #![allow(unused)]
    fn main() {
    let x = 5;

    // Ok
    let x_is_nonzero = x != 0;
    }