🆒 Rust Text §

General §

• Strings are stored using UTF-8
  • string = Vec<u8> with well formed UTF-8
  • → strings are not arrays of chars
• Strings are immutable
  • → use String for dynamic ones
    • "text".to_string()
    • format!("text")

Types §

char §

• <char> = 32-bit value holding a Unicode code point
• Functions:
  • .is_numeric(), is_alphabetic(), .is_whitespace …

str §

= Borrowed strings, fixed size

• <str>
• Create: "text"
• Multi-line: r###"text"###

Strings §

= Owned strings, dynamic size

• <String> (= wrapper around Vec<u8>, which ensures valid UTF-8)
• Create:
  • String::new()
  • "text".to_string()
  • String::with_capacity(n)

Byte Strings §

• Create: b"byte_text"

Gotchas §

Not every source of a string is guaranteed to be valid UTF-8, solutions:

• Filenames: std::path::PathBuf and &Path
• Unencoded data: Vec<u8> and &[u8]
• Env vars / cmd arguments: OsString and &OsStr