Macro dyn_fmt::dyn_write

macro_rules! dyn_write {
    ($dst:expr, $fmt:expr, $args:expr $(,)?) => { ... };
}

Writes formatted data into a buffer. A runtime analog of write! macro. In contrast with the macro format string have not be a string literal.

This macro accepts three arguments: a writer, a format string, and an arguments iterator. Arguments will be formatted according to the specified format string by calling Arguments::new(fmt, args), and the result will be passed to the writer.

The writer may be any value with a write_fmt method; generally this comes from an implementation of either the fmt::Write or the Write trait. The macro returns whatever the write_fmt method returns; commonly a fmt::Result, or an io::Result.

Examples:

use dyn_fmt::dyn_write;
use std::fmt::Write;
let mut buf = String::new();
dyn_write!(buf, "{}a{}b{}c", &[1, 2, 3]);
assert_eq!(buf, "1a2b3c");