module::implements

Macro to answer the question: does it implement a trait?

This solution has a limmitation:

• In case enity is a function and trat is Fn/FnMut/FnOnce which current entity does not implement you will get compile-time error instead of false.

Sample

println!( "implements!( 13_i32 => Copy ) : {}", implements!( 13_i32 => Copy ) );
// < implements!( 13_i32 => Copy ) : true
println!( "implements!( Box::new( 13_i32 ) => Copy ) : {}", implements!( Box::new( 13_i32 ) => Copy ) );
// < implements!( 13_i32 => Copy ) : false

Try out from the repository

git clone https://github.com/Wandalen/wTools
cd wTools
cd sample/rust/trivial
cargo run

To add to your project

cargo add implements