# Trait num_traits::CheckedSub [−] [src]

    pub trait CheckedSub: Sub<Self, Output = Self> {
        fn checked_sub(&self, v: &Self) -> Option<Self>;
    }

Performs subtraction that returns `None` instead of wrapping around on underflow.

## Required Methods

### `fn checked_sub(&self, v: &Self) -> Option<Self>`

Subtracts two numbers, checking for underflow. If underflow happens, `None` is returned.

## Implementations on Foreign Types

### `impl CheckedSub for i8`
[src]

#### `fn checked_sub(&self, v: &i8) -> Option<i8>`
[src]

### `impl CheckedSub for u64`
[src]

#### `fn checked_sub(&self, v: &u64) -> Option<u64>`
[src]

### `impl CheckedSub for usize`
[src]

#### `fn checked_sub(&self, v: &usize) -> Option<usize>`
[src]

### `impl CheckedSub for i64`
[src]

#### `fn checked_sub(&self, v: &i64) -> Option<i64>`
[src]

### `impl CheckedSub for isize`
[src]

#### `fn checked_sub(&self, v: &isize) -> Option<isize>`
[src]

### `impl CheckedSub for i32`
[src]

#### `fn checked_sub(&self, v: &i32) -> Option<i32>`
[src]

### `impl CheckedSub for u16`
[src]

#### `fn checked_sub(&self, v: &u16) -> Option<u16>`
[src]

### `impl CheckedSub for u32`
[src]

#### `fn checked_sub(&self, v: &u32) -> Option<u32>`
[src]

### `impl CheckedSub for i16`
[src]

#### `fn checked_sub(&self, v: &i16) -> Option<i16>`
[src]

### `impl CheckedSub for u8`
[src]

#### `fn checked_sub(&self, v: &u8) -> Option<u8>`
[src]

## Implementors

# Help

## Keyboard Shortcuts

`?`
  Show this help dialog
`S`
  Focus the search field
`↑`
  Move up in search results
`↓`
  Move down in search results
`↹`
  Switch tab
`⏎`
  Go to active search result
`+`
  Expand all sections
`-`
  Collapse all sections

## Search Tricks

Prefix searches with a type followed by a colon (e.g. `fn:`) to restrict the search to a given type.

Accepted types are: `fn`, `mod`, `struct`, `enum`, `trait`, `type`, `macro`, and `const`.

Search functions by type signature (e.g. `vec -> usize` or `* -> vec`)