Struct immutable_seq::lazy::Thunk

pub struct Thunk<T>(_);

A lazily evaluated value.

Methods

impl<T> Thunk<T>

fn new<F>(producer: F) -> Thunk<T> where F: FnOnce() -> ThunkResult<T> + 'static

Create a lazily evaluated value from a proc that returns that value.

You can construct Thunk's manually using this, but the lazy! macro is preferred.

let expensive = Thunk::new(|| { println!("Evaluated!"); value(7u32) });
assert_eq!(*expensive, 7u32); // "Evaluated!" gets printed here.
assert_eq!(*expensive, 7u32); // Nothing printed.

fn evaluated(val: T) -> Thunk<T>

Create a new, evaluated, thunk from a value.

fn force(&self)

Force evaluation of a thunk.

Trait Implementations

impl<T> Deref for Thunk<T>

type Target = T

The resulting type after dereferencing

fn deref(&self) -> &T

The method called to dereference a value

impl<T> Clone for Thunk<T>

fn clone(&self) -> Thunk<T>

Returns a copy of the value.

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

Performs copy-assignment from source.

impl<T> Debug for Thunk<T> where T: Debug

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

Formats the value using the given formatter.