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Debug formatting

The programmer-facing way to print a value, with {:?}.

{:?} uses a type's Debug form (quotes on text; tuples, arrays and Results print); {} uses Display, the user-facing form.

Examples

  • println!("{:?}", vec![3, 1, 2]) prints [3, 1, 2], and {:?} on a String shows its quotes and escapes, as in "Ferris\n".

See also

format string derive
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