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format string

The {} pattern that says how println! and format! show values.

A format string's {} placeholders insert values; {:?} uses Debug, and specs set width, precision, and alignment.

Examples

  • println!("{:.2}", 2.0 / 3.0) prints 0.67, and println!("{player} has {lives} lives") fills in the two variables by name.

See also

Debug formatting macro
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