compact_str/
macros.rs

1/// Creates a `CompactString` using interpolation of runtime expressions.
2///
3/// The first argument `format_compact!` receives is a format string.
4/// This must be a string literal.
5/// The power of the formatting string is in the `{}`s contained.
6///
7/// Additional parameters passed to `format_compact!` replace the `{}`s within
8/// the formatting string in the order given unless named or
9/// positional parameters are used; see [`std::fmt`] for more information.
10///
11/// A common use for `format_compact!` is concatenation and interpolation
12/// of strings.
13/// The same convention is used with [`print!`] and [`write!`] macros,
14/// depending on the intended destination of the string.
15///
16/// To convert a single value to a string, use the
17/// `ToCompactString::to_compact_string` method, which uses
18/// the [`std::fmt::Display`] formatting trait.
19///
20/// # Panics
21///
22/// `format_compact!` panics if a formatting trait implementation returns
23/// an error.
24///
25/// This indicates an incorrect implementation since
26/// `ToCompactString::to_compact_string` never returns an error itself.
27#[macro_export]
28macro_rules! format_compact {
29    ($($arg:tt)*) => {
30        $crate::ToCompactString::to_compact_string(&$crate::core::format_args!($($arg)*))
31    }
32}
33
34#[cfg(test)]
35mod tests {
36    #[test]
37    fn test_macros() {
38        assert_eq!(format_compact!("2"), "2");
39        assert_eq!(format_compact!("{}", 2), "2");
40
41        assert!(!format_compact!("2").is_heap_allocated());
42        assert!(!format_compact!("{}", 2).is_heap_allocated());
43    }
44}
compact_str/macros.rs

compact_str/
macros.rs
