Enum rustc_expand::mbe::macro_parser::MatcherLoc
source · pub(crate) enum MatcherLoc {
Token {
token: Token,
},
Delimited,
Sequence {
op: KleeneOp,
num_metavar_decls: usize,
idx_first_after: usize,
next_metavar: usize,
seq_depth: usize,
},
SequenceKleeneOpNoSep {
op: KleeneOp,
idx_first: usize,
},
SequenceSep {
separator: Token,
},
SequenceKleeneOpAfterSep {
idx_first: usize,
},
MetaVarDecl {
span: Span,
bind: Ident,
kind: Option<NonterminalKind>,
next_metavar: usize,
seq_depth: usize,
},
Eof,
}
Expand description
A unit within a matcher that a MatcherPos
can refer to. Similar to (and derived from)
mbe::TokenTree
, but designed specifically for fast and easy traversal during matching.
Notable differences to mbe::TokenTree
:
- It is non-recursive, i.e. there is no nesting.
- The end pieces of each sequence (the separator, if present, and the Kleene op) are represented explicitly, as is the very end of the matcher.
This means a matcher can be represented by &[MatcherLoc]
, and traversal mostly involves
simply incrementing the current matcher position index by one.
Variants§
Token
Delimited
Sequence
Fields
SequenceKleeneOpNoSep
SequenceSep
SequenceKleeneOpAfterSep
MetaVarDecl
Eof
Implementations§
Trait Implementations§
source§impl Clone for MatcherLoc
impl Clone for MatcherLoc
source§fn clone(&self) -> MatcherLoc
fn clone(&self) -> MatcherLoc
Returns a copy of the value. Read more
1.0.0 · source§fn clone_from(&mut self, source: &Self)
fn clone_from(&mut self, source: &Self)
Performs copy-assignment from
source
. Read moresource§impl Debug for MatcherLoc
impl Debug for MatcherLoc
source§impl Display for MatcherLoc
impl Display for MatcherLoc
source§impl PartialEq<MatcherLoc> for MatcherLoc
impl PartialEq<MatcherLoc> for MatcherLoc
source§fn eq(&self, other: &MatcherLoc) -> bool
fn eq(&self, other: &MatcherLoc) -> bool
This method tests for
self
and other
values to be equal, and is used
by ==
.impl StructuralPartialEq for MatcherLoc
Auto Trait Implementations§
impl !RefUnwindSafe for MatcherLoc
impl !Send for MatcherLoc
impl !Sync for MatcherLoc
impl Unpin for MatcherLoc
impl !UnwindSafe for MatcherLoc
Blanket Implementations§
source§impl<T> BorrowMut<T> for Twhere
T: ?Sized,
impl<T> BorrowMut<T> for Twhere T: ?Sized,
source§fn borrow_mut(&mut self) -> &mut T
fn borrow_mut(&mut self) -> &mut T
Mutably borrows from an owned value. Read more
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: 40 bytes
Size for each variant:
Token
: 31 bytesDelimited
: 0 bytesSequence
: 39 bytesSequenceKleeneOpNoSep
: 15 bytesSequenceSep
: 31 bytesSequenceKleeneOpAfterSep
: 15 bytesMetaVarDecl
: 39 bytesEof
: 0 bytes