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version requirement

The version range a Cargo.toml line allows, like "1.4" meaning 1.4.0 up to (not including) 2.0.0.

A version requirement constrains which releases Cargo may pick; a bare "1.4" is a caret requirement (^1.4 = >=1.4.0, <2.0.0) and Cargo selects the newest compatible version.

Examples

  • rand = "0.9" in Cargo.toml allows any 0.9.x but not 0.10.0; anyhow = "1.0.104" allows 1.0.104 up to, but not including, 2.0.0.

See also

semantic versioning Cargo.lock dependency
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