Constrain `usize: Add<N>`

help
1

How can I constrain a type parameter N in Rust such that it satisfies the requirement that usize implements the Add trait for N (i.e. impl<N> std::ops::Add<N> for usize)?

e.g.

fn foo<N /* usize: Add<N> */>(num: N) {
    let _ = 2usize + num;
}
2

The syntax you need is a so-called “where clause”

fn foo<N>(num: N) where usize: Add<N> {

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