# Macro collections::format [−]

    macro_rules! format {
        ( $ ( $ arg : tt ) * ) => { ... };
    }

Use the syntax described in `std::fmt` to create a value of type `String`. See `std::fmt` for more information.

# Panics

`format!` panics if a formatting trait implementation returns an error. This indicates an incorrect implementation since `fmt::Write for String` never returns an error itself.

# Examples

    format!("test");
    format!("hello {}", "world!");
    format!("x = {}, y = {y}", 10, y = 30);

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