pub fn from_fn<F>(f: F) -> FromFn<F>
🔬This is a nightly-only experimental API. (
debug_closure_helpers
)Available on crate feature
mtls
only.Expand description
Creates a type whose fmt::Debug
and fmt::Display
impls are provided with the function
f
.
§Examples
#![feature(debug_closure_helpers)]
use std::fmt;
let value = 'a';
assert_eq!(format!("{}", value), "a");
assert_eq!(format!("{:?}", value), "'a'");
let wrapped = fmt::from_fn(|f| write!(f, "{value:?}"));
assert_eq!(format!("{}", wrapped), "'a'");
assert_eq!(format!("{:?}", wrapped), "'a'");