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Rust String Slices
basicrust
Background
String slices are views into string data, enabling zero-copy substring operations in Rust.
Problem
Write a Rust function that takes a string slice and returns the first word (up to the first space) as a string slice.
Input
A string slice (&str) containing words separated by spaces.
Output
A string slice of the first word, or an empty slice if no space is found.
Sample tests
Sample 1
Input: "hello world"
Expected: "hello"
Your solution
Learning objective
Learn string slices, lifetime elision, and zero-copy substring extraction.