Struct syntex_pos::hygiene::SyntaxContext

pub struct SyntaxContext(_);

A SyntaxContext represents a chain of macro expansions (represented by marks).

Methods

impl SyntaxContext

fn empty() -> Self

fn apply_mark(self, mark: Mark) -> SyntaxContext

Extend a syntax context with a given mark

fn remove_mark(&mut self) -> Mark

fn adjust(&mut self, expansion: Mark) -> Option<Mark>

Adjust this context for resolution in a scope created by the given expansion. For example, consider the following three resolutions of f: rust 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 `Mark` from `m`. pub fn $f() {} // `$f`'s `SyntaxContext` is empty. } foo::f(); // `f`'s `SyntaxContext` has a single `Mark` 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 `Mark` 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).

fn glob_adjust(
    &mut self,
    expansion: Mark,
    glob_ctxt: SyntaxContext
) -> Option<Option<Mark>>

Adjust this context for resolution in a scope created by the given expansion via a glob import with the given SyntaxContext. For example, rust m!(f); macro m($i:ident) { mod foo { pub fn f() {} // `f`'s `SyntaxContext` has a single `Mark` 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).

fn reverse_glob_adjust(
    &mut self,
    expansion: Mark,
    glob_ctxt: SyntaxContext
) -> Option<Option<Mark>>

Undo glob_adjust if possible: rust if let Some(privacy_checking_scope) = self.reverse_glob_adjust(expansion, glob_ctxt) { assert!(self.glob_adjust(expansion, glob_ctxt) == Some(privacy_checking_scope)); }

fn modern(self) -> SyntaxContext

fn outer(self) -> Mark

Trait Implementations

impl Clone for SyntaxContext

fn clone(&self) -> SyntaxContext

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Copy for SyntaxContext

impl PartialEq for SyntaxContext

fn eq(&self, __arg_0: &SyntaxContext) -> bool

This method tests for self and other values to be equal, and is used by ==.

fn ne(&self, __arg_0: &SyntaxContext) -> bool

This method tests for !=.

impl Eq for SyntaxContext

impl Default for SyntaxContext

fn default() -> SyntaxContext

Returns the "default value" for a type.

impl PartialOrd for SyntaxContext

fn partial_cmp(&self, __arg_0: &SyntaxContext) -> Option<Ordering>

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

fn lt(&self, __arg_0: &SyntaxContext) -> bool

This method tests less than (for self and other) and is used by the < operator.

fn le(&self, __arg_0: &SyntaxContext) -> bool

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

fn gt(&self, __arg_0: &SyntaxContext) -> bool

This method tests greater than (for self and other) and is used by the > operator.

fn ge(&self, __arg_0: &SyntaxContext) -> bool

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

impl Ord for SyntaxContext

fn cmp(&self, __arg_0: &SyntaxContext) -> Ordering

This method returns an Ordering between self and other.

impl Hash for SyntaxContext

fn hash<__H: Hasher>(&self, __arg_0: &mut __H)

Feeds this value into the given [Hasher].

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

Feeds a slice of this type into the given [Hasher].

impl Debug for SyntaxContext

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

Formats the value using the given formatter.

impl Serialize for SyntaxContext

fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error> where
    S: Serializer, 

Serialize this value into the given Serde serializer.

impl<'de> Deserialize<'de> for SyntaxContext

fn deserialize<D>(deserializer: D) -> Result<Self, D::Error> where
    D: Deserializer<'de>, 

Deserialize this value from the given Serde deserializer.