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# Error code E0109

You tried to provide a generic argument to a type which doesn't need it.

Erroneous code example:

    #![allow(unused)]
    fn main() {
    type X = u32<i32>; // error: type arguments are not allowed for this type
    type Y = bool<'static>; // error: lifetime parameters are not allowed on
                            //        this type
    }

Check that you used the correct argument and that the definition is correct.

Example:

    #![allow(unused)]
    fn main() {
    type X = u32; // ok!
    type Y = bool; // ok!
    }

Note that generic arguments for enum variant constructors go after the variant, not after the enum. For example, you would write `Option::None::<u32>`, rather than `Option::<u32>::None`.