uk.ac.man.cs.rainbow.datamodel
Class Data.Union

java.lang.Object
  |
  +--uk.ac.man.cs.rainbow.rapa.data.Expression
        |
        +--uk.ac.man.cs.rainbow.datamodel.Data
              |
              +--uk.ac.man.cs.rainbow.datamodel.Data.Union

All Implemented Interfaces:

Argument, Serializable, Value, VariableContainer

Enclosing class:

Data

public static class Data.Union

extends Data

implements Serializable

Union datatypes.

See Also:

Data, Type, Type.Union, Serialized Form

Inner Class Summary

static interface

Data.Union.T What special operations must the type of a union implement?

Inner classes inherited from class uk.ac.man.cs.rainbow.datamodel.Data

Data.Comparable, Data.List, Data.Union, Data.Untyped, Data.Word

Field Summary

protected Expression	contents
protected int	index

Constructor Summary

Data.Union(Type t, Expression d, Data.Word idx)

Data.Union(Type t, Expression d, int idx)

Data.Union(Type t, Expression d, String idx)

Method Summary

Value	apply(Unifier u) Apply a unifier to this value to get a new value.
Data	cast(Type t) Return a new data value that has the given type.
boolean	equals(Data d) Standardised equality defined over data values with equal types.
Expression	getContents()
Data.Word	getIndex()
int	hashCode() Hash-code generator.
boolean	hasVariable()
boolean	occurs(Substitution s, Variable v) Check whether the variable occurs in this value under the given substitution.
protected void	setType(Type t)
Value	subst(Substitution s) Apply a substitution to this value to get a new value.
String	toString() Print the data value.
Substitution	unify(Substitution s, Value ex) Get the substitution which unifies this value with the given value, after applying the given substitution.

Methods inherited from class uk.ac.man.cs.rainbow.datamodel.Data

equals, equals, getResultType, getType, main, parse, parse, typedString

Methods inherited from class uk.ac.man.cs.rainbow.rapa.data.Expression

compatableWith, evaluate, getNodeType, subst

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Field Detail

contents

protected Expression contents

index

protected int index

Constructor Detail

Data.Union

public Data.Union(Type t,
                  Expression d,
                  int idx)
           throws TypeException

Data.Union

public Data.Union(Type t,
                  Expression d,
                  String idx)
           throws TypeException

Data.Union

public Data.Union(Type t,
                  Expression d,
                  Data.Word idx)
           throws TypeException

Method Detail

cast

public Data cast(Type t)
          throws TypeException

Description copied from class: Data

Return a new data value that has the given type.

Overrides:

cast in class Data

Following copied from class: uk.ac.man.cs.rainbow.datamodel.Data

Throws:

TypeException - Thrown if the data value being cast from (or some part of it) disgrees with the type (or type component) that is being specified for it.

toString

public String toString()

Description copied from class: Data

Print the data value.

Overrides:

toString in class Data

getContents

public Expression getContents()

getIndex

public Data.Word getIndex()

setType

protected void setType(Type t)
                throws TypeException

equals

public boolean equals(Data d)

Description copied from class: Data

Standardised equality defined over data values with equal types. Implemented by concrete subclasses.

Overrides:

equals in class Data

hashCode

public int hashCode()

Description copied from class: Data

Hash-code generator. Implemented so that data values that print the same way have the same hashCode (and ought to satisfy equals() too...)

Overrides:

hashCode in class Data

apply

public Value apply(Unifier u)

Description copied from interface: Value

Apply a unifier to this value to get a new value.

Overrides:

apply in class Data

subst

public Value subst(Substitution s)

Description copied from interface: Value

Apply a substitution to this value to get a new value.

Overrides:

subst in class Data

hasVariable

public boolean hasVariable()

Overrides:

hasVariable in class Data

occurs

public boolean occurs(Substitution s,
                      Variable v)

Description copied from interface: Value

Check whether the variable occurs in this value under the given substitution.

Overrides:

occurs in class Data

unify

public Substitution unify(Substitution s,
                          Value ex)
                   throws NotUnifiable

Description copied from interface: Value

Get the substitution which unifies this value with the given value, after applying the given substitution.

Overrides:

unify in class Data

Following copied from interface: uk.ac.man.cs.rainbow.rapa.data.Value

Parameters:

subst - The substitution to apply first.

val - The value to unify with this value.

Returns:

The substitution that is the combination of the given substitution and whatever extra substitutions are necessary to unify the two values.

Throws:

NotUnifiable - If the two values cannot be unified.