Struct Pat

pub struct Pat {
    pub id: NodeId,
    pub kind: PatKind,
    pub span: Span,
    pub tokens: Option<LazyAttrTokenStream>,
}

A match pattern.

Patterns appear in match statements and some other contexts, such as let and if let.

Fields

id: NodeId

kind: PatKind

span: Span

tokens: Option<LazyAttrTokenStream>

Implementations

impl Pat

pub fn to_ty(&self) -> Option<P<Ty>>

Attempt reparsing the pattern as a type. This is intended for use by diagnostics.

pub fn walk(&self, it: &mut impl FnMut(&Pat) -> bool)

Walk top-down and call it in each place where a pattern occurs starting with the root pattern walk is called on. If it returns false then we will descend no further but siblings will be processed.

pub fn is_rest(&self) -> bool

Is this a .. pattern?

pub fn could_be_never_pattern(&self) -> bool

Whether this could be a never pattern, taking into account that a macro invocation can return a never pattern. Used to inform errors during parsing.

pub fn contains_never_pattern(&self) -> bool

Whether this contains a ! pattern. This in particular means that a feature gate error will be raised if the feature is off. Used to avoid gating the feature twice.

pub fn descr(&self) -> Option<String>

Return a name suitable for diagnostics.

Trait Implementations

impl Clone for Pat

fn clone(&self) -> Pat

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for Pat

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

Formats the value using the given formatter.

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

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

impl DummyAstNode for Pat

fn dummy() -> Self

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

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

impl HasAttrs for Pat

const SUPPORTS_CUSTOM_INNER_ATTRS: bool = false

This is true if this HasAttrs might support ‘custom’ (proc-macro) inner attributes. Attributes like #![cfg] and #![cfg_attr] are not considered ‘custom’ attributes.

fn attrs(&self) -> &[Attribute]

fn visit_attrs(&mut self, _f: impl FnOnce(&mut AttrVec))

impl HasNodeId for Pat

fn node_id(&self) -> NodeId

fn node_id_mut(&mut self) -> &mut NodeId

impl HasTokens for Pat

fn tokens(&self) -> Option<&LazyAttrTokenStream>

fn tokens_mut(&mut self) -> Option<&mut Option<LazyAttrTokenStream>>

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: 72 bytes