Package net.hydromatic.morel.util

Class Unifier.Constraint

java.lang.Object

net.hydromatic.morel.util.Unifier.Constraint

Enclosing class:

Unifier

public static final class Unifier.Constraint
extends Object

Constraint arising from a call to an overloaded function.

Consider a call to an overloaded function with two overloads c -> d and e -> f. If the argument (a) unifies to c then the result (b) is d; if the argument unifies to e then the result is f.

This is represented as the following constraint:

 {arg: a, result: b, argResults [{c, d}, {e, f}]}
 

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static interface	Unifier.Constraint.Action	Called when a constraint is narrowed down to one possibility.

Field Summary

Fields

Modifier and Type	Field	Description
final Unifier.Variable	arg
final PairList<Unifier.Term,Unifier.Constraint.Action>	termActions

Constructor Summary

Constructors

Constructor	Description
Constraint(Unifier.Variable arg, PairList<Unifier.Term,Unifier.Constraint.Action> termActions)	Creates a Constraint.

Method Summary

Modifier and Type	Method	Description
static Unifier.Constraint.Action	equiv(Unifier.Term term1, Unifier.Term term2)	Returns an Unifier.Constraint.Action that marks two terms as equivalent.
String	toString()

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Field Details

arg

public final Unifier.Variable arg

termActions

public final PairList<Unifier.Term,Unifier.Constraint.Action> termActions

Constructor Details

Constraint

Constraint(Unifier.Variable arg,
 PairList<Unifier.Term,Unifier.Constraint.Action> termActions)

Creates a Constraint.

Method Details

equiv

public static Unifier.Constraint.Action equiv(Unifier.Term term1,
 Unifier.Term term2)

Returns an Unifier.Constraint.Action that marks two terms as equivalent.

toString

public String toString()

Overrides:

toString in class Object