Struct Context

pub struct Context { /* private fields */ }

Type inference context, or handle to a context.

Can be cheaply cloned with Context::shallow_clone. These clones will refer to the same underlying type inference context, and can be used as handles to each other. The derived Context::clone has the same effect.

There is currently no way to create an independent context with the same type inference variables (i.e. a deep clone). If you need this functionality, please file an issue.

Implementations

impl Context

pub fn new() -> Self

Creates a new empty type inference context.

pub fn alloc_free(&self, name: String) -> BoundRef

Allocate a new free type bound, and return a reference to it.

pub fn alloc_unit(&self) -> BoundRef

Allocate a new unit type bound, and return a reference to it.

pub fn alloc_complete(&self, data: Arc<Final>) -> BoundRef

Allocate a new unit type bound, and return a reference to it.

pub fn alloc_sum(&self, left: Type, right: Type) -> BoundRef

Allocate a new sum-type bound, and return a reference to it.

Panics

Panics if either of the child types are from a different inference context.

pub fn alloc_product(&self, left: Type, right: Type) -> BoundRef

Allocate a new product-type bound, and return a reference to it.

Panics

Panics if either of the child types are from a different inference context.

pub fn shallow_clone(&self) -> Self

Creates a new handle to the context.

This handle holds a reference to the underlying context and will keep it alive. The context will only be dropped once all handles, including the original context object, are dropped.

pub fn check_eq(&self, other: &Self) -> Result<(), Error>

Checks whether two inference contexts are equal, and returns an error if not.

pub fn bind_product( &self, existing: &Type, prod_l: &Type, prod_r: &Type, hint: &'static str, ) -> Result<(), Error>

Binds the type to a product bound formed by the two inner types. If this fails, attach the provided hint to the error.

Fails if the type has an existing incompatible bound.

Panics

Panics if any of the three types passed in were allocated from a different context than this one.

pub fn unify( &self, ty1: &Type, ty2: &Type, hint: &'static str, ) -> Result<(), Error>

Unify the type with another one.

Fails if the bounds on the two types are incompatible

Trait Implementations

impl Clone for Context

fn clone(&self) -> Context

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for Context

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

Formats the value using the given formatter.

impl Default for Context

fn default() -> Context

Returns the “default value” for a type.

impl PartialEq for Context

fn eq(&self, other: &Self) -> 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 Eq for Context