# Trait std::iter::Step [−] [src]

    pub trait Step: PartialOrd<Self> + Clone {
        fn steps_between(start: &Self, end: &Self) -> Option<usize>;
        fn replace_one(&mut self) -> Self;
        fn replace_zero(&mut self) -> Self;
        fn add_one(&self) -> Self;
        fn sub_one(&self) -> Self;
        fn add_usize(&self, n: usize) -> Option<Self>;
    }

🔬 This is a nightly-only experimental API. (`step_trait` #42168)

likely to be replaced by finer-grained traits

Objects that can be stepped over in both directions.

The `steps_between` function provides a way to efficiently compare two `Step` objects.

## Required Methods

### `fn steps_between(start: &Self, end: &Self) -> Option<usize>`

🔬 This is a nightly-only experimental API. (`step_trait` #42168)

likely to be replaced by finer-grained traits

Returns the number of steps between two step objects. The count is inclusive of `start` and exclusive of `end`.

Returns `None` if it is not possible to calculate `steps_between` without overflow.

### `fn replace_one(&mut self) -> Self`

🔬 This is a nightly-only experimental API. (`step_trait` #42168)

likely to be replaced by finer-grained traits

Replaces this step with `1`, returning itself

### `fn replace_zero(&mut self) -> Self`

🔬 This is a nightly-only experimental API. (`step_trait` #42168)

likely to be replaced by finer-grained traits

Replaces this step with `0`, returning itself

### `fn add_one(&self) -> Self`

🔬 This is a nightly-only experimental API. (`step_trait` #42168)

likely to be replaced by finer-grained traits

Adds one to this step, returning the result

### `fn sub_one(&self) -> Self`

🔬 This is a nightly-only experimental API. (`step_trait` #42168)

likely to be replaced by finer-grained traits

Subtracts one to this step, returning the result

### `fn add_usize(&self, n: usize) -> Option<Self>`

🔬 This is a nightly-only experimental API. (`step_trait` #42168)

likely to be replaced by finer-grained traits

Add an usize, returning None on overflow

## Implementors

- `impl Step for usize`
- `impl Step for i16`
- `impl Step for i64`
- `impl Step for i32`
- `impl Step for i128`
- `impl Step for u16`
- `impl Step for u64`
- `impl Step for isize`
- `impl Step for u32`
- `impl Step for i8`
- `impl Step for u8`
- `impl Step for u128`

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