Macro concat_string::concat_string [−][src]
macro_rules! concat_string { () => { ... }; ($($s:expr),+) => { ... }; }
Concatenates a series of string slices into an owned string.
This macro accepts zero or more arguments, where each argument implements AsRef<str>
, and
efficiently combines their string representations into a String
in order of declaration.
This is mainly useful for cases where the cost of parsing a format string outweighs the cost
of converting its arguments. Because concat_string
avoids format strings entirely, it can
achieve a higher level of performance than using format!
or other formatting utilities that
return a String
.
Example
#[macro_use(concat_string)] extern crate concat_string; fn main() { println!("{}", concat_string!("Hello", String::from(" "), "world")); }