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attribute

A note to the compiler written #[...], such as #[test].

An attribute (#[...]) attaches metadata to the next item; #[test] marks a test and #[cfg(test)] compiles an item only in test builds.

Examples

  • #[test] marks a test function, and #[cfg(test)] compiles the tests module only for cargo test.

See also

test conditional compilation derive lint level
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