Enum NoConstantGenericsReason

pub(crate) enum NoConstantGenericsReason {
    NonTrivialConstArg,
    IsEnumDiscriminant,
}

Reason for why an anon const is not allowed to reference generic parameters

Variants

NonTrivialConstArg

Const arguments are only allowed to use generic parameters when:

• feature(generic_const_exprs) is enabled or
• the const argument is a sole const generic parameter, i.e. foo::<{ N }>()

If neither of the above are true then this is used as the cause.

IsEnumDiscriminant

Enum discriminants are not allowed to reference generic parameters ever, this is used when an anon const is in the following position:

enum Foo<const N: isize> {
    Variant = { N }, // this anon const is not allowed to use generics
}

Trait Implementations

impl Clone for NoConstantGenericsReason

fn clone(&self) -> NoConstantGenericsReason

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for NoConstantGenericsReason

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl PartialEq for NoConstantGenericsReason

fn eq(&self, other: &NoConstantGenericsReason) -> bool

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

fn ne(&self, other: &Rhs) -> bool

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

impl Copy for NoConstantGenericsReason

impl Eq for NoConstantGenericsReason

impl StructuralPartialEq for NoConstantGenericsReason

Layout

Note: Most layout information is completely unstable and may even differ between compilations. The only exception is types with certain repr(...) attributes. Please see the Rust Reference's “Type Layout” chapter for details on type layout guarantees.

Size: 1 byte

Size for each variant:

• NonTrivialConstArg: 0 bytes
• IsEnumDiscriminant: 0 bytes