Crate slice_fill

Slice::fill prototype.

C++ ships with std::fill which fills a range of memory with a given byte. Rust currently doesn't have a standard library equivalent for that.

Issue 2067 on the RFCs repo proposes a safe wrapper around memset(3) call. This is a reference implementation of the API proposed in the issue that optimizes to memset in many cases but leaves the exact performance profile undisclosed.

As Rust makes progress on specialization this can later be lifted to guarantee the fastest known implementation is used for any specific type. But until then it provides a convenient API to fill slices of memory with repeating patterns, which will generally be optimized to be very fast already.

Examples

use slice_fill::SliceExt;

let mut buf = vec![0; 10];
buf.fill(1);
assert_eq!(buf, vec![1; 10]);

Further reading

• The hunt for the fastest zero
• Filling large arrays with zeroes quickly in C
• Godbolt ASM output

Traits

SliceExt

Extension trait for std::slice.