Structural unifier for compiler types. More...

#include <tpl_constraints.H>

Collaboration diagram for Aleph::Compiler_Type_Unifier:

Public Member Functions
	Compiler_Type_Unifier (Compiler_Type_Context &ctx) noexcept
	Constructs a unifier operating over `ctx`.

void	clear () noexcept
	Clears substitutions and the last stored result.

const Compiler_Unify_Result &	last_result () const noexcept
	Returns the last result produced by `unify()` or `solve()`.

const Compiler_Type_Substitution &	substitution () const noexcept
	Returns the accumulated substitution.

Compiler_Type_Id	apply (const Compiler_Type_Id id)
	Applies the current substitution to `id`.

Compiler_Unify_Result	unify (const Compiler_Type_Id lhs, const Compiler_Type_Id rhs)
	Attempts to unify `lhs` and `rhs`.

Compiler_Unify_Result	solve (const Compiler_Type_Constraint_Set &constraints)
	Solves a whole ordered set of type constraints.

std::string	dump_substitution ()
	Dumps the current substitution in a deterministic format.

Private Member Functions
Compiler_Unify_Result	fail (const Compiler_Unify_Result_Kind kind, const Compiler_Type_Id lhs, const Compiler_Type_Id rhs, const std::string &message, const Source_Span &span={}) noexcept

Compiler_Type_Id	resolve (const Compiler_Type_Id id) const

bool	occurs_in (const Compiler_Type_Id variable, const Compiler_Type_Id candidate)

Compiler_Unify_Result	bind_variable (const Compiler_Type_Id variable, const Compiler_Type_Id replacement)

Static Private Member Functions
static Compiler_Unify_Result	success () noexcept

Private Attributes
Compiler_Type_Context *	context = nullptr

Compiler_Type_Substitution	subst

Compiler_Unify_Result	last

Detailed Description

Structural unifier for compiler types.

Definition at line 378 of file tpl_constraints.H.

Constructor & Destructor Documentation

◆ Compiler_Type_Unifier()

Aleph::Compiler_Type_Unifier::Compiler_Type_Unifier ( Compiler_Type_Context & ctx )

inlineexplicitnoexcept

Constructs a unifier operating over ctx.

Definition at line 493 of file tpl_constraints.H.

Member Function Documentation

◆ apply()

Compiler_Type_Id Aleph::Compiler_Type_Unifier::apply ( const Compiler_Type_Id id )

inline

Applies the current substitution to id.

Parameters

id	Type to normalize.

Returns: Normalized type id.

Definition at line 521 of file tpl_constraints.H.

References Aleph::Compiler_Type_Substitution::apply(), context, and subst.

Referenced by Aleph::Compiler_Typed_Semantic_Analyzer::collect_free_type_variables(), Aleph::Compiler_Typed_Semantic_Analyzer::instantiate_binding(), Aleph::Compiler_Typed_Semantic_Analyzer::instantiate_type(), main(), Aleph::Compiler_Typed_Semantic_Analyzer::normalize_recorded_types(), TEST(), TEST(), TEST(), and TEST().

◆ bind_variable()

Compiler_Unify_Result Aleph::Compiler_Type_Unifier::bind_variable	(	const Compiler_Type_Id	variable,
		const Compiler_Type_Id	replacement
	)

inlineprivate

Definition at line 464 of file tpl_constraints.H.

References Aleph::Compiler_Type_Substitution::bind(), Aleph::blossom_maximum_cardinality_matching(), context, fail(), Aleph::Occurs_Check_Failed, occurs_in(), resolve(), Aleph::Rigid_Variable, subst, success(), Aleph::Compiler_Type_Context::to_string(), and Aleph::Compiler_Type_Context::type().

Referenced by unify().

◆ clear()

void Aleph::Compiler_Type_Unifier::clear ( )

inlinenoexcept

Clears substitutions and the last stored result.

Definition at line 498 of file tpl_constraints.H.

References Aleph::Compiler_Type_Substitution::clear(), last, and subst.

Referenced by Aleph::Compiler_Typed_Semantic_Analyzer::clear().

◆ dump_substitution()

std::string Aleph::Compiler_Type_Unifier::dump_substitution ( )

inline

Dumps the current substitution in a deterministic format.

Definition at line 653 of file tpl_constraints.H.

References context, subst, and Aleph::Compiler_Type_Substitution::to_string().

Referenced by main(), and TEST().

◆ fail()

Compiler_Unify_Result Aleph::Compiler_Type_Unifier::fail	(	const Compiler_Unify_Result_Kind	kind,
		const Compiler_Type_Id	lhs,
		const Compiler_Type_Id	rhs,
		const std::string &	message,
		const Source_Span &	span = `{}`
	)

inlineprivatenoexcept

Definition at line 391 of file tpl_constraints.H.

Referenced by bind_variable(), and unify().

◆ last_result()

const Compiler_Unify_Result & Aleph::Compiler_Type_Unifier::last_result ( ) const

inlinenoexcept

Returns the last result produced by unify() or solve().

Definition at line 505 of file tpl_constraints.H.

References last.

◆ occurs_in()

bool Aleph::Compiler_Type_Unifier::occurs_in	(	const Compiler_Type_Id	variable,
		const Compiler_Type_Id	candidate
	)

inlineprivate

Definition at line 425 of file tpl_constraints.H.

References Aleph::blossom_maximum_cardinality_matching(), Aleph::Builtin, context, Aleph::Enum, Aleph::Function, occurs_in(), resolve(), Aleph::Struct, Aleph::Tuple, Aleph::Compiler_Type_Context::type(), and Aleph::Type_Variable.

Referenced by bind_variable(), and occurs_in().

◆ resolve()

Compiler_Type_Id Aleph::Compiler_Type_Unifier::resolve ( const Compiler_Type_Id id ) const

inlineprivate

Definition at line 407 of file tpl_constraints.H.

References ah_logic_error_if, Aleph::Compiler_Type_Substitution::lookup(), Aleph::Compiler_Type_Substitution::size(), and subst.

Referenced by bind_variable(), occurs_in(), and unify().

◆ solve()

Compiler_Unify_Result Aleph::Compiler_Type_Unifier::solve ( const Compiler_Type_Constraint_Set & constraints )

inline

Solves a whole ordered set of type constraints.

Constraints are solved in insertion order and the first failing result is returned with the corresponding span.

Parameters

constraints Ordered equality constraints.

Returns: Final success result or the first failure encountered.

Definition at line 632 of file tpl_constraints.H.

References Aleph::blossom_maximum_cardinality_matching(), Aleph::Constraint_Set< T >::constraint(), last, Aleph::Equality_Constraint< T >::lhs, Aleph::Equality_Constraint< T >::message, Aleph::Equality_Constraint< T >::rhs, Aleph::Constraint_Set< T >::size(), Aleph::Equality_Constraint< T >::span, success(), and unify().

Referenced by main(), TEST(), and TEST().

◆ substitution()

const Compiler_Type_Substitution & Aleph::Compiler_Type_Unifier::substitution ( ) const

inlinenoexcept

Returns the accumulated substitution.

Definition at line 511 of file tpl_constraints.H.

References subst.

◆ success()

static Compiler_Unify_Result Aleph::Compiler_Type_Unifier::success ( )

inlinestaticprivatenoexcept

Definition at line 385 of file tpl_constraints.H.

Referenced by bind_variable(), solve(), and unify().

◆ unify()

Compiler_Unify_Result Aleph::Compiler_Type_Unifier::unify	(	const Compiler_Type_Id	lhs,
		const Compiler_Type_Id	rhs
	)

inline

Attempts to unify lhs and rhs.

On success, the internal substitution is updated.

Parameters

lhs	Left-hand type.
rhs	Right-hand type.

Returns: Success or the first detected failure.

Definition at line 534 of file tpl_constraints.H.

References Aleph::Arity_Mismatch, bind_variable(), Aleph::blossom_maximum_cardinality_matching(), Aleph::Builtin, context, Aleph::Enum, fail(), Aleph::Function, Aleph::Invalid_Type, Aleph::Kind_Mismatch, last, resolve(), Aleph::Struct, success(), Aleph::Compiler_Type_Context::to_string(), Aleph::Tuple, Aleph::Compiler_Type_Context::type(), Aleph::Type_Variable, and unify().

Referenced by Aleph::Compiler_Typed_Semantic_Analyzer::require_unify(), solve(), TEST(), TEST(), TEST(), TEST(), and unify().

Member Data Documentation

◆ context

Compiler_Type_Context* Aleph::Compiler_Type_Unifier::context = nullptr

private

Definition at line 380 of file tpl_constraints.H.

Referenced by apply(), bind_variable(), dump_substitution(), occurs_in(), and unify().

◆ last

Compiler_Unify_Result Aleph::Compiler_Type_Unifier::last

private

Definition at line 382 of file tpl_constraints.H.

Referenced by clear(), last_result(), solve(), and unify().

◆ subst

Compiler_Type_Substitution Aleph::Compiler_Type_Unifier::subst

private

Definition at line 381 of file tpl_constraints.H.

Referenced by apply(), bind_variable(), clear(), dump_substitution(), resolve(), and substitution().

The documentation for this class was generated from the following file:

tpl_constraints.H

Public Member Functions

Private Member Functions

Static Private Member Functions

Private Attributes

Detailed Description

Constructor & Destructor Documentation

◆ Compiler_Type_Unifier()

Member Function Documentation

◆ apply()

◆ bind_variable()

◆ clear()

◆ dump_substitution()

◆ fail()

◆ last_result()

◆ occurs_in()

◆ resolve()

◆ solve()

◆ substitution()

◆ success()

◆ unify()

Member Data Documentation

◆ context

◆ last

◆ subst