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#![forbid(warnings)]
#![forbid(unused)]
#![forbid(box_pointers)]
#![forbid(missing_copy_implementations)]
#![forbid(missing_debug_implementations)]
#![forbid(missing_docs)]
#![forbid(trivial_casts)]
#![forbid(trivial_numeric_casts)]
#![forbid(unsafe_code)]
#![forbid(unused_extern_crates)]
#![forbid(unused_import_braces)]
#![forbid(unused_qualifications)]
#![forbid(unused_results)]
#![forbid(variant_size_differences)]
#![cfg_attr(feature = "cargo-clippy", forbid(clippy))]
#![cfg_attr(feature = "cargo-clippy", forbid(clippy_pedantic))]
#![cfg_attr(feature = "cargo-clippy", forbid(clippy_cargo))]
#![cfg_attr(feature = "cargo-clippy", forbid(clippy_complexity))]
#![cfg_attr(feature = "cargo-clippy", forbid(clippy_correctness))]
#![cfg_attr(feature = "cargo-clippy", forbid(clippy_perf))]
#![cfg_attr(feature = "cargo-clippy", forbid(clippy_style))]
#[macro_export]
macro_rules! concat_string {
() => { String::with_capacity(0) };
($($s:expr),+) => {{
use std::ops::AddAssign;
let mut len = 0;
$(len.add_assign(AsRef::<str>::as_ref(&$s).len());)+
let mut buf = String::with_capacity(len);
$(buf.push_str($s.as_ref());)+
buf
}};
}
#[cfg(test)]
mod tests {
#[test]
fn concat_string_0_args() {
let s = concat_string!();
assert_eq!(s, String::from(""));
}
#[test]
fn concat_string_1_arg() {
let s = concat_string!("foo");
assert_eq!(s, String::from("foo"));
}
#[test]
fn concat_string_str_string() {
let s = concat_string!("foo", String::from("bar"));
assert_eq!(s, String::from("foobar"));
}
}