Class FmtBy

crates/rustc_codegen_spirv/src/linker/specializer.rs:66–66

FIXME(eddyb) move this elsewhere.

// FIXME(eddyb) move this elsewhere.
struct FmtBy<F: Fn(&mut fmt::Formatter<'_>) -> fmt::Result>(F);

impl<F: Fn(&mut fmt::Formatter<'_>) -> fmt::Result> fmt::Debug for FmtBy<F> {
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {