Macro cglue_macro::check

check!() { /* proc-macro */ }

Check if the group can be cast to the specified traits.

The syntax is similar to a cast expression, but uses impl keyword:

check!(obj impl Trait1 + Trait2 + Trait3);

The result of check! will be a boolean value.

This macro accepts either:

1. A list of optional traits, without any mandatory traits.

or

2. A list of optional traits, with every mandatory trait.

In either case a successfully cast object will still implement the mandatory traits.