core::convert::From - Rust
Description: API documentation for the Rust `From` trait in crate `core`.
Keywords: rust, rustlang, rust-lang, From

# Trait core::convert::From 1.0.0 [−] [src]

    pub trait From<T>: Sized {
        fn from(_: T) -> Self;
    }

Construct `Self` via a conversion.

Note: this trait must not fail. If the conversion can fail, use `TryFrom` or a dedicated method which returns an `Option<T>` or a `Result<T, E>`.

# Examples

`String` implements `From<&str>`:

    let string = "hello".to_string();
    let other_string = String::from("hello");

    assert_eq!(string, other_string);Run

# Generic impls

- `From<T> for U` implies `Into<U>``for T`
- `from()` is reflexive, which means that `From<T> for T` is implemented

## Required Methods

### `fn from(_: T) -> Self`

Performs the conversion.

## Implementors

- `impl From<u8> for u16`
- `impl From<u8> for u32`
- `impl From<u8> for u64`
- `impl From<u8> for u128`
- `impl From<u8> for usize`
- `impl From<u16> for u32`
- `impl From<u16> for u64`
- `impl From<u16> for u128`
- `impl From<u32> for u64`
- `impl From<u32> for u128`
- `impl From<u64> for u128`
- `impl From<i8> for i16`
- `impl From<i8> for i32`
- `impl From<i8> for i64`
- `impl From<i8> for i128`
- `impl From<i8> for isize`
- `impl From<i16> for i32`
- `impl From<i16> for i64`
- `impl From<i16> for i128`
- `impl From<i32> for i64`
- `impl From<i32> for i128`
- `impl From<i64> for i128`
- `impl From<u8> for i16`
- `impl From<u8> for i32`
- `impl From<u8> for i64`
- `impl From<u8> for i128`
- `impl From<u16> for i32`
- `impl From<u16> for i64`
- `impl From<u16> for i128`
- `impl From<u32> for i64`
- `impl From<u32> for i128`
- `impl From<u64> for i128`
- `impl From<i8> for f32`
- `impl From<i8> for f64`
- `impl From<i16> for f32`
- `impl From<i16> for f64`
- `impl From<i32> for f64`
- `impl From<u8> for f32`
- `impl From<u8> for f64`
- `impl From<u16> for f32`
- `impl From<u16> for f64`
- `impl From<u32> for f64`
- `impl From<f32> for f64`
- `impl<T> From<T> for T`
- `impl<T: Copy> From<T> for Cell<T>`
- `impl<T> From<T> for RefCell<T>`
- `impl<T> From<T> for UnsafeCell<T>`
- `impl From<char> for u32`
- `impl From<u8> for char`
- `impl<T> From<T> for Option<T>`

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