# Function metadata

Source

    pub const fn metadata<T: PointeeSized>(
        ptr: *const T,
    ) -> <T as Pointee>::Metadata

🔬This is a nightly-only experimental API. (`ptr_metadata` #81513)
Expand description

Extracts the metadata component of a pointer.

Values of type `*mut T`, `&T`, or `&mut T` can be passed directly to this function as they implicitly coerce to `*const T`.

## §Example

    #![feature(ptr_metadata)]

    assert_eq!(std::ptr::metadata("foo"), 3_usize);