PhantomInvariant in std::marker - Rust (original) (raw)

Struct PhantomInvariant

pub struct PhantomInvariant<T>(/* private fields */)
where
    T: ?Sized;

🔬This is a nightly-only experimental API. (phantom_variance_markers #135806)

Expand description

Zero-sized type used to mark a type parameter as invariant.

Types that are both passed as an argument and used as part of the return value from a function are invariant. See the reference for more information.

§Layout

For all T, the following are guaranteed:

size_of::<PhantomInvariant<T>>() == 0
align_of::<PhantomInvariant<T>>() == 1

Source §

Source

🔬This is a nightly-only experimental API. (phantom_variance_markers #135806)

Constructs a new instance of the variance marker.

Source §

Tests for self and other values to be equal, and is used by ==.

1.0.0 · Source §

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

Source §

This method returns an ordering between self and other values if one exists. Read more

1.0.0 · Source §

Tests less than (for self and other) and is used by the < operator. Read more

1.0.0 · Source §

Tests less than or equal to (for self and other) and is used by the<= operator. Read more

1.0.0 · Source §

Tests greater than (for self and other) and is used by the >operator. Read more

1.0.0 · Source §

Tests greater than or equal to (for self and other) and is used by the >= operator. Read more

Source §