Trait ResultExt

pub trait ResultExt<T, E> {
    // Required methods
    fn tap_mut(self, f: impl FnOnce(&mut T)) -> Result<T, E>;
    fn tap_err_mut(self, f: impl FnOnce(&mut E)) -> Result<T, E>;
    fn swap(self) -> Result<E, T>;
}

Extension methods for std::result::Result.

Required Methods

fn tap_mut(self, f: impl FnOnce(&mut T)) -> Result<T, E>

Tap into a Result and modify its Ok value.

This method captures the Result in order not to break the caller-chain.

Example

use rs_std_ext::result::ResultExt;
 
let mut x: Result<String, usize> = Ok("4".into());
assert_eq!(x.tap_mut(|s| s.push('2')), Ok("42".into()));

fn tap_err_mut(self, f: impl FnOnce(&mut E)) -> Result<T, E>

Tap into a Result and modify its Err value.

This method captures the Result in order not to break the caller-chain.

Example

use rs_std_ext::result::ResultExt;
 
let mut x: Result<String, usize> = Err(40);
assert_eq!(x.tap_err_mut(|s| *s += 2), Err(42));

fn swap(self) -> Result<E, T>

Swap the Ok and Err values of a Result.

Example

use rs_std_ext::result::ResultExt;
 
let x: Result<&str, usize> = Ok("foo");
assert_eq!(x.swap(), Err("foo"));

Dyn Compatibility

This trait is not dyn compatible.

In older versions of Rust, dyn compatibility was called "object safety", so this trait is not object safe.

Implementations on Foreign Types

impl<T, E> ResultExt<T, E> for Result<T, E>

fn tap_mut(self, f: impl FnOnce(&mut T)) -> Result<T, E>

fn tap_err_mut(self, f: impl FnOnce(&mut E)) -> Result<T, E>

fn swap(self) -> Result<E, T>

Implementors