Crate fn_name

Macros that produce the name of the function they’re invoked within.

Uninstantiated Names

The uninstantiated! macro produces the name of the surrounding function or method, without generics instantiated; e.g.:

struct GenericType<A>(A);

impl<A> GenericType<A> {
    fn generic_method<B>(self, _: B) -> &'static str {
        fn_name::uninstantiated!()
    }
}

fn main() {
    assert_eq!(
        GenericType(42u8).generic_method(false),
        "GenericType<_>::generic_method"
    );
}

Instantiated Names

The instantiated! macro produces the name of the surrounding function or method, including instantiated generics (if any); e.g.:

struct GenericType<A>(A);

impl<A> GenericType<A> {
    fn generic_method<B>(self, _: B) -> &'static str {
        fn_name::instantiated!()
    }
}

fn main() {
    assert_eq!(
        GenericType(42u8).generic_method(false),
        "GenericType<u8>::generic_method<bool>"
    );
}

Limitations

The expansion of these macros is not (yet) const evaluable; their implementations rely on core::any::type_name, which is not a const fn.

Macros

instantiated

Produces the name of the surrounding function or method, including instantiated generics (if any).

uninstantiated

Produces the name of the surrounding function or method, without generics instantiated.