# Trait std::ops::Shl 1.0.0[−][src]

The left shift operator `<<`

. Note that because this trait is implemented
for all integer types with multiple right-hand-side types, Rust’s type
checker has special handling for `_ << _`

, setting the result type for
integer operations to the type of the left-hand-side operand. This means
that though `a << b`

and `a.shl(b)`

are one and the same from an evaluation
standpoint, they are different when it comes to type inference.

# Examples

An implementation of `Shl`

that lifts the `<<`

operation on integers to a
wrapper around `usize`

.

use std::ops::Shl; #[derive(PartialEq, Debug)] struct Scalar(usize); impl Shl<Scalar> for Scalar { type Output = Self; fn shl(self, Self(rhs): Self) -> Self::Output { let Self(lhs) = self; Self(lhs << rhs) } } assert_eq!(Scalar(4) << Scalar(2), Scalar(16));Run

An implementation of `Shl`

that spins a vector leftward by a given amount.

use std::ops::Shl; #[derive(PartialEq, Debug)] struct SpinVector<T: Clone> { vec: Vec<T>, } impl<T: Clone> Shl<usize> for SpinVector<T> { type Output = Self; fn shl(self, rhs: usize) -> Self::Output { // Rotate the vector by `rhs` places. let (a, b) = self.vec.split_at(rhs); let mut spun_vector = vec![]; spun_vector.extend_from_slice(b); spun_vector.extend_from_slice(a); Self { vec: spun_vector } } } assert_eq!(SpinVector { vec: vec![0, 1, 2, 3, 4] } << 2, SpinVector { vec: vec![2, 3, 4, 0, 1] });Run