Enum Constraint

pub enum Constraint {
    Variant {
        ty: TypeId,
        variant: VariantId,
        fields: TupleIndex,
    },
    ConstInt {
        val: i128,
        ty: TypeId,
    },
    ConstPrim {
        val: Sym,
    },
    Some,
}

Pattern matches which can fail. Some binding sites are the result of successfully matching a constraint. A rule applies constraints to binding sites to determine whether the rule matches.

Variants

Variant

The value must match this enum variant.

Fields

ty: TypeId

Which enum type is being matched? This is implied by the binding where the constraint is applied, but recorded here for convenience.

variant: VariantId

Which enum variant must this binding site match to satisfy the rule?

fields: TupleIndex

Number of fields in this variant of this enum. This is recorded in the constraint for convenience, to avoid needing to look up the variant in a sema::TypeEnv.

ConstInt

The value must equal this integer literal.

Fields

val: i128

The constant value.

ty: TypeId

The constant’s type. Unsigned types preserve the representation of val, not its value.

ConstPrim

The value must equal this Rust primitive value.

Fields

val: Sym

The constant value.

Some

The value must be an Option::Some, from a fallible extractor.

Implementations

impl Constraint

pub fn bindings_for(self, source: BindingId) -> Vec<Binding>

Return the nested Bindings from matching the given Constraint against the given BindingId.

Trait Implementations

impl Clone for Constraint

fn clone(&self) -> Constraint

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for Constraint

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

Formats the value using the given formatter.

impl Hash for Constraint

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 Constraint

fn cmp(&self, other: &Constraint) -> 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 Constraint

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

fn partial_cmp(&self, other: &Constraint) -> 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 Copy for Constraint

impl Eq for Constraint

impl StructuralPartialEq for Constraint