// run-pass#![allow(unused_variables)]// Test that you can supply `&F` where `F: Fn()`.#![feature(lang_items)]fna<F:Fn()-> i32>(f: F)-> i32{f()}fnb(f: &dynFn()-> i32)-> i32{a(f)}fnc<F:Fn()-> i32>(f: &F)-> i32{a(f)}fnmain(){letz: isize=7;letx=b(&||22);assert_eq!(x,22);letx=c(&||22);assert_eq!(x,22);}