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Trait std::str::FromStr

pub trait FromStr {
    type Err;
    fn from_str(s: &str) -> Result<Self, Self::Err>;
}

A trait to abstract the idea of creating a new instance of a type from a string.

FromStr's from_str() method is often used implicitly, through str's parse() method. See parse()'s documentation for examples.

Associated Types

The associated error which can be returned from parsing.

Required Methods

Parses a string s to return a value of this type.

If parsing succeeds, return the value inside Ok, otherwise when the string is ill-formatted return an error specific to the inside Err. The error type is specific to implementation of the trait.

Examples

Basic usage with i32, a type that implements FromStr:

use std::str::FromStr;

let s = "5";
let x = i32::from_str(s).unwrap();

assert_eq!(5, x);

Implementors

© 2010 The Rust Project Developers
Licensed under the Apache License, Version 2.0 or the MIT license, at your option.
https://doc.rust-lang.org/std/str/trait.FromStr.html