Debug
Debug is a Rust standard-library trait for formatting values in programmer-oriented diagnostic representations.
Refactoring to Rust
The Debug trait is a Rust formatting trait for producing developer-oriented representations of values.
- How it is used
- Supports developer-oriented error output when Result values are unwrapped or expected to panic.
- How deep it goes
- Defines developer representation and demonstrates enum derivation, but defers deeper trait details.
- Examples
- Uses a FizzBuzz Error enum with GotNegative, #[derive(Debug)], unwrap(), expect(), and panic output.
- What you can do after
- Apply it via #[derive(Debug)] so Rust errors can be printed by unwrap() and expect().
Learn Rust in a Month of Lunches
Debug is the Rust trait for producing programmer-oriented representations of values.
- How it is used
- Uses programmer-oriented output to inspect values when Display formatting is unavailable or insufficient.
- How deep it goes
- Explains format choices, compiler guidance, pretty output, and derive(Debug), but defers manual fmt implementation.
- Examples
- Uses the unit value (), compiler error E0277, and a User structure to contrast ordinary and pretty Debug output.
- What you can do after
- Apply Debug via println! using {:?}, {:#?}, and #[derive(Debug)] to inspect values.
Related concepts
- traitkind of · A trait is a type-level construct that defines reusable behavior or members that types can implement or compose.
- println! macroused by · The println! macro is an output operation that formats arguments and writes the resulting text followed by a line terminator to standard output.
- derive macroconfigured by · A Rust derive macro is an attribute that automatically generates implementations of specified traits or related functionality for a type.
- Displaycontrasts with · Display is Rust’s standard formatting trait for producing a user-facing textual representation of a value.
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