Struct TypeSubstitution 

pub struct TypeSubstitution { /* private fields */ }

A substitution map from type parameter names to concrete types.

Implementations

impl TypeSubstitution

pub fn new() -> Self

Create an empty substitution.

pub fn from_args( interner: &dyn TypeDatabase, type_params: &[TypeParamInfo], type_args: &[TypeId], ) -> Self

Create a substitution from type parameters and arguments.

type_params - The declared type parameters (e.g., <T, U>) type_args - The provided type arguments (e.g., <string, number>)

When type_args has fewer elements than type_params, default values from the type parameters are used for the remaining parameters.

IMPORTANT: Defaults may reference earlier type parameters, so they need to be instantiated with the substitution built so far.

pub fn insert(&mut self, name: Atom, type_id: TypeId)

Add a single substitution.

pub fn get(&self, name: Atom) -> Option<TypeId>

Look up a substitution.

pub fn is_empty(&self) -> bool

Check if substitution is empty.

pub fn len(&self) -> usize

Number of substitutions.

pub const fn map(&self) -> &FxHashMap<Atom, TypeId>

Get a reference to the internal substitution map.

This is useful for building new substitutions based on existing ones.

Trait Implementations

impl Clone for TypeSubstitution

fn clone(&self) -> TypeSubstitution

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for TypeSubstitution

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

Formats the value using the given formatter.

impl Default for TypeSubstitution

fn default() -> TypeSubstitution

Returns the “default value” for a type.