macro_rules! strwriter_as_str {
($expr:expr) => { ... };
}
đź‘ŽDeprecated since 0.2.19: Use
StrWriter::as_str_alt
insteadExpand description
Converts a &'static StrWriter
to a &'static str
, in a const
/static
initializer.
This is usable in const
or static
initializers,
but not inside of const fn
s.
Deprecated: This macro is deprecated because
the StrWriter::as_str_alt
method
allows converting a&'static StrWriter
to a &'static str
.
§Runtime
If the “rust_1_64” feature is disabled,
this takes time proportional to $expr.capacity() - $expr.len()
.
If the “rust_1_64” feature is enabled, it takes constant time to run.
§Example
use const_format::StrWriter;
use const_format::{strwriter_as_str, unwrap, writec};
const CAP: usize = 128;
const __STR: &StrWriter = &{
let mut writer = StrWriter::new([0; CAP]);
// Writing the array with debug formatting, and the integers with hexadecimal formatting.
unwrap!(writec!(writer, "{:x}", [3u32, 5, 8, 13, 21, 34]));
writer
};
const STR: &str = strwriter_as_str!(__STR);
fn main() {
assert_eq!(STR, "[3, 5, 8, d, 15, 22]");
}