Enum Transparency

pub enum Transparency {
    Transparent,
    SemiOpaque,
    Opaque,
}

A property of a macro expansion that determines how identifiers produced by that expansion are resolved.

Variants

Transparent

Identifier produced by a transparent expansion is always resolved at call-site. Call-site spans in procedural macros, hygiene opt-out in macro should use this.

SemiOpaque

Identifier produced by a semi-opaque expansion may be resolved either at call-site or at definition-site. If it’s a local variable, label or $crate then it’s resolved at def-site. Otherwise it’s resolved at call-site. macro_rules macros behave like this, built-in macros currently behave like this too, but that’s an implementation detail.

Opaque

Identifier produced by an opaque expansion is always resolved at definition-site. Def-site spans in procedural macros, identifiers from macro by default use this.

Implementations

impl Transparency

pub fn fallback(macro_rules: bool) -> Self

Trait Implementations

impl Clone for Transparency

fn clone(&self) -> Transparency

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for Transparency

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

Formats the value using the given formatter.

impl<__D: SpanDecoder> Decodable<__D> for Transparency

fn decode(__decoder: &mut __D) -> Self

impl<__E: SpanEncoder> Encodable<__E> for Transparency

fn encode(&self, __encoder: &mut __E)

impl Hash for Transparency

fn hash<__H: Hasher>(&self, state: &mut __H)

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl<__CTX> HashStable<__CTX> for Transparency

where __CTX: HashStableContext,

fn hash_stable(&self, __hcx: &mut __CTX, __hasher: &mut StableHasher)

impl PartialEq for Transparency

fn eq(&self, other: &Transparency) -> 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 PartialOrd for Transparency

fn partial_cmp(&self, other: &Transparency) -> Option<Ordering>

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

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

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

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

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

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

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

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

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

impl Copy for Transparency

impl Eq for Transparency

impl StructuralPartialEq for Transparency

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:

• Transparent: 0 bytes
• SemiOpaque: 0 bytes
• Opaque: 0 bytes