Trait num::Num

[+] Show declaration

pub trait Num: Zero + One + NumOps<Self, Self> + PartialEq<Self> {
    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

type FromStrRadixErr

Required methods

fn from_str_radix(str: &str, radix: u32) -> Result<Self, Self::FromStrRadixErr>[−]

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

impl<T> Num for Wrapping<T> where
    T: Num,
    Wrapping<T>: Mul<Wrapping<T>>,
    Wrapping<T>: Add<Wrapping<T>>,
    Wrapping<T>: Div<Wrapping<T>>,
    Wrapping<T>: Rem<Wrapping<T>>,
    Wrapping<T>: Sub<Wrapping<T>>,
    <Wrapping<T> as Add<Wrapping<T>>>::Output == Wrapping<T>,
    <Wrapping<T> as Sub<Wrapping<T>>>::Output == Wrapping<T>,
    <Wrapping<T> as Mul<Wrapping<T>>>::Output == Wrapping<T>,
    <Wrapping<T> as Div<Wrapping<T>>>::Output == Wrapping<T>,
    <Wrapping<T> as Rem<Wrapping<T>>>::Output == Wrapping<T>, [−]

[+] Show hidden undocumented items

type FromStrRadixErr = <T as Num>::FromStrRadixErr

fn from_str_radix(
    str: &str,
    radix: u32
) -> Result<Wrapping<T>, <Wrapping<T> as Num>::FromStrRadixErr>

Implementors

impl Num for f32[+]

[+] Show hidden undocumented items

type FromStrRadixErr = ParseFloatError

fn from_str_radix(
    src: &str,
    radix: u32
) -> Result<f32, <f32 as Num>::FromStrRadixErr>

impl Num for f64[+]

[+] Show hidden undocumented items

type FromStrRadixErr = ParseFloatError

fn from_str_radix(
    src: &str,
    radix: u32
) -> Result<f64, <f64 as Num>::FromStrRadixErr>

impl Num for i8[+]

[+] Show hidden undocumented items

type FromStrRadixErr = ParseIntError

fn from_str_radix(s: &str, radix: u32) -> Result<i8, ParseIntError>

impl Num for i16[+]

[+] Show hidden undocumented items

type FromStrRadixErr = ParseIntError

fn from_str_radix(s: &str, radix: u32) -> Result<i16, ParseIntError>

impl Num for i32[+]

[+] Show hidden undocumented items

type FromStrRadixErr = ParseIntError

fn from_str_radix(s: &str, radix: u32) -> Result<i32, ParseIntError>

impl Num for i64[+]

[+] Show hidden undocumented items

type FromStrRadixErr = ParseIntError

fn from_str_radix(s: &str, radix: u32) -> Result<i64, ParseIntError>

impl Num for i128[+]

[+] Show hidden undocumented items

type FromStrRadixErr = ParseIntError

fn from_str_radix(s: &str, radix: u32) -> Result<i128, ParseIntError>

impl Num for isize[+]

[+] Show hidden undocumented items

type FromStrRadixErr = ParseIntError

fn from_str_radix(s: &str, radix: u32) -> Result<isize, ParseIntError>

impl Num for u8[+]

[+] Show hidden undocumented items

type FromStrRadixErr = ParseIntError

fn from_str_radix(s: &str, radix: u32) -> Result<u8, ParseIntError>

impl Num for u16[+]

[+] Show hidden undocumented items

type FromStrRadixErr = ParseIntError

fn from_str_radix(s: &str, radix: u32) -> Result<u16, ParseIntError>

impl Num for u32[+]

[+] Show hidden undocumented items

type FromStrRadixErr = ParseIntError

fn from_str_radix(s: &str, radix: u32) -> Result<u32, ParseIntError>

impl Num for u64[+]

[+] Show hidden undocumented items

type FromStrRadixErr = ParseIntError

fn from_str_radix(s: &str, radix: u32) -> Result<u64, ParseIntError>

impl Num for u128[+]

[+] Show hidden undocumented items

type FromStrRadixErr = ParseIntError

fn from_str_radix(s: &str, radix: u32) -> Result<u128, ParseIntError>

impl Num for usize[+]

[+] Show hidden undocumented items

type FromStrRadixErr = ParseIntError

fn from_str_radix(s: &str, radix: u32) -> Result<usize, ParseIntError>

impl<T> Num for Complex<T> where
    T: Clone + Num, [+]

type FromStrRadixErr = ParseComplexError<<T as Num>::FromStrRadixErr>

fn from_str_radix(
    s: &str,
    radix: u32
) -> Result<Complex<T>, <Complex<T> as Num>::FromStrRadixErr>[−]

Parses a +/- bi; ai +/- b; a; or bi where a and b are of type T

impl<T> Num for Ratio<T> where
    T: Clone + Integer, [+]

type FromStrRadixErr = ParseRatioError

fn from_str_radix(s: &str, radix: u32) -> Result<Ratio<T>, ParseRatioError>[−]

Parses numer/denom where the numbers are in base radix.

impl<T: Num + Clone> Num for Complex<T>

impl<T: Clone + Integer> Num for Ratio<T>