Trait num_traits::Num[][src]

pub trait Num: PartialEq + Zero + One + NumOps {
    type FromStrRadixErr;
    fn from_str_radix(
        str: &str,
        radix: u32
    ) -> Result<Self, Self::FromStrRadixErr>; }
Expand description

The base trait for numeric types, covering 0 and 1 values, comparisons, basic numeric operations, and string conversion.

Associated Types

Required methods

Convert from a string and radix (typically 2..=36).

Examples

use num_traits::Num;

let result = <i32 as Num>::from_str_radix("27", 10);
assert_eq!(result, Ok(27));

let result = <i32 as Num>::from_str_radix("foo", 10);
assert!(result.is_err());

Supported radices

The exact range of supported radices is at the discretion of each type implementation. For primitive integers, this is implemented by the inherent from_str_radix methods in the standard library, which panic if the radix is not in the range from 2 to 36. The implementation in this crate for primitive floats is similar.

For third-party types, it is suggested that implementations should follow suit and at least accept 2..=36 without panicking, but an Err may be returned for any unsupported radix. It’s possible that a type might not even support the common radix 10, nor any, if string parsing doesn’t make sense for that type.

Implementations on Foreign Types

Implementors

impl Num for BigInt

impl Num for BigUint