variant_count in std::intrinsics - Rust
Description: Returns the number of variants of the type `T` cast to a `usize`; if `T` has no variants, returns `0`. Uninhabited variants will be counted.

## variant_count

# Function variant_count

Source

    pub const fn variant_count<T>() -> usize

🔬This is a nightly-only experimental API. (`core_intrinsics`)
Expand description

Returns the number of variants of the type `T` cast to a `usize`; if `T` has no variants, returns `0`. Uninhabited variants will be counted.

Note that, unlike most intrinsics, this can only be called at compile-time as backends do not have an implementation for it. The only caller (its stable counterpart) wraps this intrinsic call in a `const` block so that backends only see an evaluated constant.

The to-be-stabilized version of this intrinsic is `crate::mem::variant_count`.