Attribute Macro cfg_version 

#[cfg_version]

Conditionally include an item based on a dependency’s resolved version.

Uses Cargo’s semver syntax for version requirements. Only considers direct dependencies of the current crate.

Examples

use cfg_version::cfg_version;

#[cfg_version(indexmap = "^2.8")]
fn needs_indexmap_2_8() { }

#[cfg_version(indexmap = ">=2, <3")]
fn needs_indexmap_2_x() { }

#[cfg_version(indexmap = "<2.8")]
fn old_indexmap_fallback() { }

If the dependency is not present in the current crate’s dependencies, the item is excluded.