rust / intermediate
Snippet
Slices and String Slice Basics
String slices (&str) are a borrowed reference to a sequence of UTF-8 bytes. They can point to part of a String or directly to string literal data in the binary. Using &str in function signatures allows your functions to accept both owned Strings and borrowed string slices without modification.
snippet.rs
rust
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fn first_word(s: &str) -> &str {let bytes = s.as_bytes();for (i, &byte) in bytes.iter().enumerate() {if byte == b' ' {return &s[0..i];}}s}fn main() {let text = String::from("Hello Rustaceans");let word = first_word(&text);println!("First word: {}", word);let literal = "Hello OpenCode";let word2 = first_word(literal);println!("First word: {}", word2);}
Breakdown
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fn first_word(s: &str) -> &str
Accepts both &String and &str due to Deref coercion
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let bytes = s.as_bytes();
Converts string to byte array for byte-level iteration
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for (i, &byte) in bytes.iter().enumerate()
Iterates with index using enumerate
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if byte == b' '
Checks for space character using byte literal b' '
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return &s[0..i]
Returns slice from start to space position