# Using chain Function in Rust

> Source: <https://www.dotnetperls.com/2026_10_17_using-chain-function-rust>
> Published: 2026-10-17 07:00:00+00:00

Recently I used Gemini 4 Argon to **generate** a **Rust function** that parses data in a `Vector`. To find words, it used `iter` on the `Vector`. It called the `chain` function on that iterator to add another element—a space returned by calling `std::iter::once`.

By using `chain` and `iter::once` in this way, the loop could **iterate past the end** of the `Vector` in an elegant way. The last word could be handled in the same way as the other words. I felt this solution was **clear** and helped **reduce code bloat**—no extra code after the loop was required. It seems that using `chain` and `iter::once` is a useful approach to certain looping tasks in Rust.