Struct ScopeSet 

pub struct ScopeSet(/* private fields */);

A set of hygiene scopes, kept sorted and deduplicated so that subset tests are a merge.

The empty set is the source program’s own scope, which is why an ordinary top-level definition is visible everywhere: {} ⊆ S for every S.

Implementations

impl ScopeSet

pub fn empty() -> ScopeSet

pub fn is_empty(&self) -> bool

pub fn len(&self) -> usize

pub fn contains(&self, s: Scope) -> bool

pub fn insert(&self, s: Scope) -> ScopeSet

pub fn remove(&self, s: Scope) -> ScopeSet

pub fn flip(&self, s: Scope) -> ScopeSet

Add the scope if absent, remove it if present.

This is the operation that makes hygiene work: the expander adds a fresh scope to a macro’s input and flips it on the output, so identifiers that came from the call site come back to their original scopes while identifiers the template introduced acquire the new one.

pub fn is_subset_of(&self, other: &ScopeSet) -> bool

self ⊆ other. A binding is a candidate for a reference exactly when this holds.

Trait Implementations

impl Clone for ScopeSet

fn clone(&self) -> ScopeSet

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for ScopeSet

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

Formats the value using the given formatter.

impl Default for ScopeSet

fn default() -> ScopeSet

Returns the “default value” for a type.

impl Hash for ScopeSet

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 Ord for ScopeSet

fn cmp(&self, other: &ScopeSet) -> Ordering

This method returns an Ordering between self and other.

fn max(self, other: Self) -> Self

where Self: Sized,

Compares and returns the maximum of two values.

fn min(self, other: Self) -> Self

where Self: Sized,

Compares and returns the minimum of two values.

fn clamp(self, min: Self, max: Self) -> Self

where Self: Sized,

Restrict a value to a certain interval.

impl PartialEq for ScopeSet

fn eq(&self, other: &ScopeSet) -> 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 ScopeSet

fn partial_cmp(&self, other: &ScopeSet) -> 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 Eq for ScopeSet

impl StructuralPartialEq for ScopeSet