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Slice types

SliceType :
   [ Type ]

A slice is a dynamically sized type representing a 'view' into a sequence of elements of type T. The slice type is written as [T].

To use a slice type it generally has to be used behind a pointer for example as:

  • &[T], a 'shared slice', often just called a 'slice', it doesn't own the data it points to, it borrows it.
  • &mut [T], a 'mutable slice', mutably borrows the data it points to.
  • Box<[T]>, a 'boxed slice'


# #![allow(unused_variables)]
#fn main() {
// A heap-allocated array, coerced to a slice
let boxed_array: Box<[i32]> = Box::new([1, 2, 3]);

// A (shared) slice into an array
let slice: &[i32] = &boxed_array[..];

All elements of slices are always initialized, and access to a slice is always bounds-checked in safe methods and operators.