emmiegit / rust-ref-map Goto Github PK

Rust crate for convenience traits on Option<T> and Result<T, E>.

Has no dependencies, and should work on any Rust release channel.

Three methods are provided, ref_map() for Some(_) and Ok(_), and ref_map_err() for Err(_). This allows easily mapping borrowed values from maybe values.

use ref_map::*;

let string: Option<String> = Some("hello world\n".into());

// Without ref-map:
// the .as_ref() is necessary because otherwise it tries to consume the String
let message: Option<&str> = string.as_ref().map(|s| s.trim());

// With ref-map:
let message: Option<&str> = string.ref_map(|s| s.trim());

ref_map() is also provided for Result<T, E> for Ok, and ref_map_err() for Err.

Copyright (C) 2020-2021 Ammon Smith

Available under the MIT License.