Attribute Macro stability::unstable

#[unstable]

Mark an API as unstable.

You can apply this attribute to an item in your public API that you would like to expose to users, but are not yet ready for general use. This is useful when you want to let users try out some new functionality for an API you haven't finished testing or designing, or for whatever reason do not want to commit any stability guarantees for.

This attribute does the following things to annotated items:

• Changes the visibility of the item from pub to pub(crate), unless a certain crate feature is enabled.
• Appends an "Availability" section to the item's documentation that notes that the item is unstable, and indicates the name of the crate feature to enable it.

Note that unlike the #[unstable] attribute used in the standard library, this attribute does not apply itself recursively to child items.

Applying this attribute to non-pub items is pointless and does nothing.

Arguments

The unstable attribute supports optional arguments that can be passed to control its behavior.

• feature: Specify the name of the unstable feature that should control this item's availability. The crate feature will have the string unstable- prepended to it. If not specified, it will be guarded by a catch-all unstable feature.

Examples

/// This function does something really risky!
///
/// Don't use it yet!
#[stability::unstable(feature = "risky-function")]
pub fn risky_function() {
    unimplemented!()
}