mutually_exclusive_features 0.1.0

Macros to check that only none or one of a set of features is enabled at a time, as known as mutually exclusive features
Documentation

Mutually Exclusive Features

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Macros to check mutually exclusive features in Rust

It contains none_or_one_of and exactly_one_of macros.

Both check mutually exclusive features in Rust, but none_or_one_of allows for no features to be enabled, while exactly_one_of requires exactly one feature to be enabled.

Usage

none_or_one_of

Call it with the list of features you want to be mutually exclusive:

use mutually_exclusive_features::none_or_one_of;
none_or_one_of!("feature1", "feature2", "feature3");

Which will generate the following code:

#[cfg(all(feature="feature1", feature="feature2"))]
compile_error!("The `feature1` and `feature2` features are mutually exclusive and cannot be enabled at the same time!");

#[cfg(all(feature="feature1", feature="feature3"))]
compile_error!("The `feature1` and `feature3` features are mutually exclusive and cannot be enabled at the same time!");

#[cfg(all(feature="feature2", feature="feature3"))]
compile_error!("The `feature2` and `feature3` features are mutually exclusive and cannot be enabled at the same time!");

exactly_one_of

It's the same, but requires exactly one feature to be enabled:

use mutually_exclusive_features::exactly_one_of;
exactly_one_of!("feature1", "feature2", "feature3");

Which will generate the following code:

#[cfg(all(feature="feature1", feature="feature2"))]
compile_error!("The `feature1` and `feature2` features are mutually exclusive and cannot be enabled at the same time!");

#[cfg(all(feature="feature1", feature="feature3"))]
compile_error!("The `feature1` and `feature3` features are mutually exclusive and cannot be enabled at the same time!");

#[cfg(all(feature="feature2", feature="feature3"))]
compile_error!("The `feature2` and `feature3` features are mutually exclusive and cannot be enabled at the same time!");

#[cfg(not(any(feature="feature1", feature="feature2", feature="feature3")))]
compile_error!("You must enable exactly one of `feature1`, `feature2`, `feature3` features!");