Slices

A slice gives you a view into a larger collection:

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  • Slices borrow data from the sliced type.

Speaker Notes

This slide should take about 7 minutes.
  • We create a slice by borrowing a and specifying the starting and ending indexes in brackets.

  • If the slice starts at index 0, Rust’s range syntax allows us to drop the starting index, meaning that &a[0..a.len()] and &a[..a.len()] are identical.

  • The same is true for the last index, so &a[2..a.len()] and &a[2..] are identical.

  • To easily create a slice of the full array, we can therefore use &a[..].

  • s is a reference to a slice of i32s. Notice that the type of s (&[i32]) no longer mentions the array length. This allows us to perform computation on slices of different sizes.

  • Slices always borrow from another object. In this example, a has to remain ‘alive’ (in scope) for at least as long as our slice.