8b6a431b3d
Boost iterator intersperse(_with) performance I did some benchmark digging into the `intersperse` and `intersperse_with` code as part of [this discussion](https://internals.rust-lang.org/t/add-iterate-with-separators-iterator-function/18781/13), and as a result I optimized them a bit, without relying on the peekable iterator. See also [full benchmark repo](https://github.com/nyurik/intersperse_perf) Benchmarks show near 2x performance improvements with the simple `sum` [benchmarks](https://gist.github.com/nyurik/68b6c9b3d90f0d14746d4186bf8fa1e2):  |
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| Cargo.toml | ||
