std​::result

Enums

Result

Functions

collect
fold
fold_
[src]

Enum std::result::Result

pub enum Result<T, E> {
    Ok(T),
    Err(E),
}

Result is a type that represents either success (Ok) or failure (Err).

Variants

Ok

Contains the success value

Err

Contains the error value

Methods

impl<T, E> Result<T, E>

fn is_ok(&self) -> bool

Returns true if the result is Ok

fn is_err(&self) -> bool

Returns true if the result is Err

fn ok(self) -> Option<T>

Convert from Result<T, E> to Option<T>

fn err(self) -> Option<E>

Convert from Result<T, E> to Option<E>

fn as_ref<'r>(&'r self) -> Result<&'r T, &'r E>

Convert from Result<T, E> to Result<&T, &E>

fn as_mut<'r>(&'r mut self) -> Result<&'r mut T, &'r mut E>

Convert from Result<T, E> to Result<&mut T, &mut E>

fn map<U>(self, op: |T| -> U) -> Result<U, E>

Maps a Result<T, E> to Result<U, E> by applying a function to an contained Ok value, leaving an Err value untouched.

This function can be used to compose the results of two functions.

Example:

let res = read_file(file).map(|buf| {
    parse_bytes(buf)
})

fn map_err<F>(self, op: |E| -> F) -> Result<T, F>

Maps a Result<T, E> to Result<T, F> by applying a function to an contained Err value, leaving an Ok value untouched.

This function can be used to pass through a successful result while handling an error.

fn and<U>(self, res: Result<U, E>) -> Result<U, E>

Returns res if the result is Ok, otherwise returns the Err value of self.

fn and_then<U>(self, op: |T| -> Result<U, E>) -> Result<U, E>

Calls op if the result is Ok, otherwise returns the Err value of self.

This function can be used for control flow based on result values

fn or(self, res: Result<T, E>) -> Result<T, E>

Returns res if the result is Err, otherwise returns the Ok value of self.

fn or_else<F>(self, op: |E| -> Result<T, F>) -> Result<T, F>

Calls op if the result is Err, otherwise returns the Ok value of self.

This function can be used for control flow based on result values

fn unwrap(self) -> T

Unwraps a result, yielding the content of an Ok. Fails if the value is an Err.

fn unwrap_err(self) -> E

Unwraps a result, yielding the content of an Err. Fails if the value is an Ok.

Trait Implementations

Derived Implementations

impl<T: Show, E: Show> Show for Result<T, E>

fn fmt(&self, __arg_0: &mut Formatter) -> Result

Formats the value using the given formatter.

impl<T: TotalOrd, E: TotalOrd> TotalOrd for Result<T, E>

fn cmp(&self, __arg_0: &Result<T, E>) -> Ordering

impl<T: TotalEq, E: TotalEq> TotalEq for Result<T, E>

fn assert_receiver_is_total_eq(&self)

impl<T: Ord, E: Ord> Ord for Result<T, E>

fn lt(&self, __arg_0: &Result<T, E>) -> bool

fn le(&self, __arg_0: &Result<T, E>) -> bool

fn gt(&self, __arg_0: &Result<T, E>) -> bool

fn ge(&self, __arg_0: &Result<T, E>) -> bool

impl<T: Eq, E: Eq> Eq for Result<T, E>

fn eq(&self, __arg_0: &Result<T, E>) -> bool

fn ne(&self, __arg_0: &Result<T, E>) -> bool

impl<T: Clone, E: Clone> Clone for Result<T, E>

fn clone(&self) -> Result<T, E>

Returns a copy of the value. The contents of owned pointers are copied to maintain uniqueness, while the contents of managed pointers are not copied.

fn clone_from(&mut self, source: &Self)

Perform copy-assignment from source.

a.clone_from(&b) is equivalent to a = b.clone() in functionality, but can be overridden to reuse the resources of a to avoid unnecessary allocations.