Struct rustc_span::hygiene::SyntaxContext
source · pub struct SyntaxContext(u32);
Expand description
A SyntaxContext
represents a chain of pairs (ExpnId, Transparency)
named “marks”.
Tuple Fields§
§0: u32
Implementations§
source§impl SyntaxContext
impl SyntaxContext
pub const fn root() -> Self
pub const fn is_root(self) -> bool
pub(crate) const fn as_u32(self) -> u32
pub(crate) const fn from_u32(raw: u32) -> SyntaxContext
sourcepub(crate) fn apply_mark(
self,
expn_id: ExpnId,
transparency: Transparency
) -> SyntaxContext
pub(crate) fn apply_mark( self, expn_id: ExpnId, transparency: Transparency ) -> SyntaxContext
Extend a syntax context with a given expansion and transparency.
sourcepub fn remove_mark(&mut self) -> ExpnId
pub fn remove_mark(&mut self) -> ExpnId
Pulls a single mark off of the syntax context. This effectively moves the context up one macro definition level. That is, if we have a nested macro definition as follows:
macro_rules! f {
macro_rules! g {
...
}
}
and we have a SyntaxContext that is referring to something declared by an invocation of g (call it g1), calling remove_mark will result in the SyntaxContext for the invocation of f that created g1. Returns the mark that was removed.
pub fn marks(self) -> Vec<(ExpnId, Transparency)>
sourcepub fn adjust(&mut self, expn_id: ExpnId) -> Option<ExpnId>
pub fn adjust(&mut self, expn_id: ExpnId) -> Option<ExpnId>
Adjust this context for resolution in a scope created by the given expansion.
For example, consider the following three resolutions of f
:
#![feature(decl_macro)]
mod foo { pub fn f() {} } // `f`'s `SyntaxContext` is empty.
m!(f);
macro m($f:ident) {
mod bar {
pub fn f() {} // `f`'s `SyntaxContext` has a single `ExpnId` from `m`.
pub fn $f() {} // `$f`'s `SyntaxContext` is empty.
}
foo::f(); // `f`'s `SyntaxContext` has a single `ExpnId` from `m`
//^ Since `mod foo` is outside this expansion, `adjust` removes the mark from `f`,
//| and it resolves to `::foo::f`.
bar::f(); // `f`'s `SyntaxContext` has a single `ExpnId` from `m`
//^ Since `mod bar` not outside this expansion, `adjust` does not change `f`,
//| and it resolves to `::bar::f`.
bar::$f(); // `f`'s `SyntaxContext` is empty.
//^ Since `mod bar` is not outside this expansion, `adjust` does not change `$f`,
//| and it resolves to `::bar::$f`.
}
This returns the expansion whose definition scope we use to privacy check the resolution,
or None
if we privacy check as usual (i.e., not w.r.t. a macro definition scope).
sourcepub fn normalize_to_macros_2_0_and_adjust(
&mut self,
expn_id: ExpnId
) -> Option<ExpnId>
pub fn normalize_to_macros_2_0_and_adjust( &mut self, expn_id: ExpnId ) -> Option<ExpnId>
Like SyntaxContext::adjust
, but also normalizes self
to macros 2.0.
sourcepub fn glob_adjust(
&mut self,
expn_id: ExpnId,
glob_span: Span
) -> Option<Option<ExpnId>>
pub fn glob_adjust( &mut self, expn_id: ExpnId, glob_span: Span ) -> Option<Option<ExpnId>>
Adjust this context for resolution in a scope created by the given expansion
via a glob import with the given SyntaxContext
.
For example:
#![feature(decl_macro)]
m!(f);
macro m($i:ident) {
mod foo {
pub fn f() {} // `f`'s `SyntaxContext` has a single `ExpnId` from `m`.
pub fn $i() {} // `$i`'s `SyntaxContext` is empty.
}
n!(f);
macro n($j:ident) {
use foo::*;
f(); // `f`'s `SyntaxContext` has a mark from `m` and a mark from `n`
//^ `glob_adjust` removes the mark from `n`, so this resolves to `foo::f`.
$i(); // `$i`'s `SyntaxContext` has a mark from `n`
//^ `glob_adjust` removes the mark from `n`, so this resolves to `foo::$i`.
$j(); // `$j`'s `SyntaxContext` has a mark from `m`
//^ This cannot be glob-adjusted, so this is a resolution error.
}
}
This returns None
if the context cannot be glob-adjusted.
Otherwise, it returns the scope to use when privacy checking (see adjust
for details).
sourcepub fn reverse_glob_adjust(
&mut self,
expn_id: ExpnId,
glob_span: Span
) -> Option<Option<ExpnId>>
pub fn reverse_glob_adjust( &mut self, expn_id: ExpnId, glob_span: Span ) -> Option<Option<ExpnId>>
Undo glob_adjust
if possible:
if let Some(privacy_checking_scope) = self.reverse_glob_adjust(expansion, glob_ctxt) {
assert!(self.glob_adjust(expansion, glob_ctxt) == Some(privacy_checking_scope));
}
pub fn hygienic_eq(self, other: SyntaxContext, expn_id: ExpnId) -> bool
pub fn normalize_to_macros_2_0(self) -> SyntaxContext
pub fn normalize_to_macro_rules(self) -> SyntaxContext
pub fn outer_expn(self) -> ExpnId
sourcepub fn outer_expn_data(self) -> ExpnData
pub fn outer_expn_data(self) -> ExpnData
ctxt.outer_expn_data()
is equivalent to but faster than
ctxt.outer_expn().expn_data()
.
pub fn outer_mark(self) -> (ExpnId, Transparency)
pub fn dollar_crate_name(self) -> Symbol
pub fn edition(self) -> Edition
Trait Implementations§
source§impl Clone for SyntaxContext
impl Clone for SyntaxContext
source§fn clone(&self) -> SyntaxContext
fn clone(&self) -> SyntaxContext
1.0.0 · source§fn clone_from(&mut self, source: &Self)
fn clone_from(&mut self, source: &Self)
source
. Read moresource§impl Debug for SyntaxContext
impl Debug for SyntaxContext
source§impl Hash for SyntaxContext
impl Hash for SyntaxContext
source§impl<CTX: HashStableContext> HashStable<CTX> for SyntaxContext
impl<CTX: HashStableContext> HashStable<CTX> for SyntaxContext
fn hash_stable(&self, ctx: &mut CTX, hasher: &mut StableHasher)
source§impl Ord for SyntaxContext
impl Ord for SyntaxContext
source§fn cmp(&self, other: &SyntaxContext) -> Ordering
fn cmp(&self, other: &SyntaxContext) -> Ordering
1.21.0 · source§fn max(self, other: Self) -> Selfwhere
Self: Sized,
fn max(self, other: Self) -> Selfwhere Self: Sized,
source§impl PartialEq<SyntaxContext> for SyntaxContext
impl PartialEq<SyntaxContext> for SyntaxContext
source§fn eq(&self, other: &SyntaxContext) -> bool
fn eq(&self, other: &SyntaxContext) -> bool
self
and other
values to be equal, and is used
by ==
.source§impl PartialOrd<SyntaxContext> for SyntaxContext
impl PartialOrd<SyntaxContext> for SyntaxContext
source§fn partial_cmp(&self, other: &SyntaxContext) -> Option<Ordering>
fn partial_cmp(&self, other: &SyntaxContext) -> Option<Ordering>
1.0.0 · source§fn le(&self, other: &Rhs) -> bool
fn le(&self, other: &Rhs) -> bool
self
and other
) and is used by the <=
operator. Read moreimpl Copy for SyntaxContext
impl Eq for SyntaxContext
impl StructuralEq for SyntaxContext
impl StructuralPartialEq for SyntaxContext
Auto Trait Implementations§
impl RefUnwindSafe for SyntaxContext
impl Send for SyntaxContext
impl Sync for SyntaxContext
impl Unpin for SyntaxContext
impl UnwindSafe for SyntaxContext
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
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: 4 bytes