hlt.language.design.types

Class DefinedType

java.lang.Object

hlt.language.design.types.Type

hlt.language.design.types.StaticType

hlt.language.design.types.NamedType

hlt.language.design.types.TypeTerm

hlt.language.design.types.DefinedType

All Implemented Interfaces:

Valuable, java.lang.Cloneable

public class DefinedType
extends TypeTerm

This is the class of defined opaque types. This is a new type hiding the type that defines it. In other words, it acts as a wrapper for the defining type, and behaves as an entirely new type in that it will not unify against anything except itself or a type parameter.

Look in Tables for the methods that will define a new opaque type (DefineNewType(...)).

See Also:

TypeDefinition, Tables

Field Summary

Fields inherited from class hlt.language.design.types.Type

ARRAY, BAG, BOOLEAN, BOXABLE, CHAR, CLASS, COLLECTION, CONSTANT, DEFINED, FUNCTION, INT, INT_RANGE, INT_SORT, LIST, NAMED_TUPLE, OBJECT_SORT, PARAMETER, REAL, REAL_RANGE, REAL_SORT, SET, STRING, TUPLE, VOID, VOID_SORT

Constructor Summary

Constructors

Constructor and Description
DefinedType(java.lang.String name, Type definition) Constructs a non-polymorphic defined type with the specified name and definition.
DefinedType(java.lang.String name, Type definition, java.util.AbstractList arguments)
DefinedType(java.lang.String name, Type definition, Type[] arguments) Constructs a polymorphic defined type with the specified name, definition, and type parameters.

Method Summary

Methods

Modifier and Type	Method and Description
Type	actualType() Returns the value of this when this does not have a defining type; or that of its defining type otherwise.
void	checkOccurrence(TypeParameter parameter, Type context, TypeChecker typeChecker) Throws a FailedUnificationException if the specified type parameter occurs in this type.
Type	copy(java.util.HashMap parameters) Returns a copy of this type with a consistent renaming of all free type parameters, and identyfing bound type parameters with their values.
void	curry(int depth, TypeChecker typeChecker) If this this a function type, transforms the type by splitting the domains at the specified depth, and records the old form in the appropriate trail of the specified type-checker for undoing purposes.
Type	definition()
int	eqCode() Returns a hash code for this type - the reason for using the name eqCode (rather than overriding hashCode), is that it is important to preserve the implementation of java.lang.Object.hashCode for type parameters (to be compatible with ==).
Type	flatten() Returns a flattened form of this type by uncurrying all the domains of all function types that occur in it.
java.util.HashSet	getParameters(java.util.HashSet set) Returns the specified set augmented with all the unbound type parameters that occur in this type.
Type	instantiate(java.util.HashMap substitution) Returns a copy of this type with all free type parameters bound as per the specified type substitution.
boolean	isBoxedType() This returns true iff this type has been marked as boxed (true by default - overridden by TypeConstant).
boolean	isPolymorphic()
byte	kind() This returns the value identifying what kind of type this is.
int	numberOfTypeComponents() Returns the number of type components making up this type.
Type	setBoxed(boolean flag) With true (resp.
DefinedType	setDefinition(Type type)
void	setTypeRefComponent(int n, Type type) Sets the n-th undereferenced type component of this type to the specified type; throws a NoSuchTypeComponentException otherwise.
byte	sort() This returns the runtime sort for this type (OBJECT_SORT by default - overridden by TypeConstant).
Type	typeRefComponent(int n) Returns the n-th undereferenced type component in this type, if any; throws a NoSuchTypeComponentException otherwise.
boolean	unify(Type type) This unifies this type with the specified type with no possibility of undoing any effects.
void	unify(Type type, TypeChecker typeChecker) Normally, a defined type can only unify against a type parameter or itself.

Methods inherited from class hlt.language.design.types.TypeTerm

argument, arguments, arity, isEqualTo, isEqualTo, setArguments, setArguments, toString

Methods inherited from class hlt.language.design.types.NamedType

name, setName

Methods inherited from class hlt.language.design.types.Type

array, array, baseType, baseTypeRef, BOOLEAN, BOXED_BOOLEAN, BOXED_CHAR, BOXED_INT, BOXED_REAL, boxSort, CHAR, copy, equals, findValue, getParameters, getValue, INT, is, isBag, isBoolean, isChar, isCollection, isGlobalUnsafe, isInt, isList, isPrimitive, isReal, isSet, isString, isVoid, kindString, rank, REAL, resetNames, shadowType, standardize, toFullString, toQuantifiedString, toQuantifiedString, typeComponent, unwrapper, value, wrapper

Methods inherited from class java.lang.Object

getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Detail

DefinedType

public DefinedType(java.lang.String name,
           Type definition)

Constructs a non-polymorphic defined type with the specified name and definition.

DefinedType

public DefinedType(java.lang.String name,
           Type definition,
           Type[] arguments)

Constructs a polymorphic defined type with the specified name, definition, and type parameters.

DefinedType

public DefinedType(java.lang.String name,
           Type definition,
           java.util.AbstractList arguments)

Method Detail

numberOfTypeComponents

public int numberOfTypeComponents()

Description copied from class: Type

Returns the number of type components making up this type.

Overrides:

numberOfTypeComponents in class TypeTerm

typeRefComponent

public Type typeRefComponent(int n)
                      throws NoSuchTypeComponentException

Description copied from class: Type

Returns the n-th undereferenced type component in this type, if any; throws a NoSuchTypeComponentException otherwise.

Overrides:

typeRefComponent in class TypeTerm

Throws:

NoSuchTypeComponentException

setTypeRefComponent

public void setTypeRefComponent(int n,
                       Type type)
                         throws NoSuchTypeComponentException

Description copied from class: Type

Sets the n-th undereferenced type component of this type to the specified type; throws a NoSuchTypeComponentException otherwise.

Overrides:

setTypeRefComponent in class TypeTerm

Throws:

NoSuchTypeComponentException

actualType

public final Type actualType()

Description copied from class: Type

Returns the value of this when this does not have a defining type; or that of its defining type otherwise. This is overriden in DefinedType.

Overrides:

actualType in class Type

definition

public final Type definition()

setDefinition

public final DefinedType setDefinition(Type type)

kind

public final byte kind()

Description copied from class: Type

This returns the value identifying what kind of type this is.

Specified by:

kind in class Type

isPolymorphic

public final boolean isPolymorphic()

Overrides:

isPolymorphic in class TypeTerm

sort

public final byte sort()

Description copied from class: Type

This returns the runtime sort for this type (OBJECT_SORT by default - overridden by TypeConstant).

N.B.: The following definition specifies only the default behavior for this method. Specific subclasses are generally expected to override this method.

Overrides:

sort in class Type

isBoxedType

public final boolean isBoxedType()

Description copied from class: Type

This returns true iff this type has been marked as boxed (true by default - overridden by TypeConstant).

N.B.: The following definition specifies only the default behavior for this method. Specific subclasses are generally expected to override this method.

Overrides:

isBoxedType in class Type

setBoxed

public final Type setBoxed(boolean flag)

Description copied from class: Type

With true (resp. false), this marks this type as boxed (resp., unboxed), if it is boxable. Does nothing by default.

N.B.: The following definition specifies only the default behavior for this method. Specific subclasses are generally expected to override this method.

Overrides:

setBoxed in class Type

unify

public final void unify(Type type,
         TypeChecker typeChecker)
                 throws FailedUnificationException

Normally, a defined type can only unify against a type parameter or itself. However, if the type-checking mode allows it, opaque types whose actual type is a (named) tuple type will unify against similar raw tuple types.

Overrides:

unify in class TypeTerm

Throws:

FailedUnificationException

unify

public final boolean unify(Type type)

Description copied from class: Type

This unifies this type with the specified type with no possibility of undoing any effects. This method is meant to be used on types that are fresh copies independent of any type-checker because it will side-effect the structures it traverses. It returns true iff unification succeeds. NB: This method does not perform the "occurs-check" test.

Overrides:

unify in class TypeTerm

checkOccurrence

public final void checkOccurrence(TypeParameter parameter,
                   Type context,
                   TypeChecker typeChecker)
                           throws FailedUnificationException

Description copied from class: Type

Throws a FailedUnificationException if the specified type parameter occurs in this type. The type context is the outermost type enclosing this.

N.B.: The following definition specifies only the default behavior for this method. Specific subclasses are generally expected to override this method.

Overrides:

checkOccurrence in class TypeTerm

Throws:

FailedUnificationException

getParameters

public final java.util.HashSet getParameters(java.util.HashSet set)

Description copied from class: Type

Returns the specified set augmented with all the unbound type parameters that occur in this type.

Overrides:

getParameters in class TypeTerm

curry

public final void curry(int depth,
         TypeChecker typeChecker)

Description copied from class: Type

If this this a function type, transforms the type by splitting the domains at the specified depth, and records the old form in the appropriate trail of the specified type-checker for undoing purposes. For example, currying A[1],...,A[n]n -> A at depth k (A[k+1],...,A[n] -> A). If this type is a type parameter, this will curry its value if any. Otherwise, does nothing.

N.B.: The following definition specifies only the default behavior for this method. Specific subclasses are generally expected to override this method.

Overrides:

curry in class Type

flatten

public final Type flatten()

Description copied from class: Type

Returns a flattened form of this type by uncurrying all the domains of all function types that occur in it. It also trims all binding chains of type parameters that may occur in it. The form returned is the canonical form used for all types of defined symbols and is assumed for type equality tests to work.

N.B.: The following definition specifies only the default behavior for this method. Specific subclasses are generally expected to override this method.

Overrides:

flatten in class TypeTerm

copy

public final Type copy(java.util.HashMap parameters)

Description copied from class: Type

Returns a copy of this type with a consistent renaming of all free type parameters, and identyfing bound type parameters with their values.

N.B.: The following definition specifies only the default behavior for this method. Specific subclasses are generally expected to override this method.

Overrides:

copy in class TypeTerm

instantiate

public final Type instantiate(java.util.HashMap substitution)

Description copied from class: Type

Returns a copy of this type with all free type parameters bound as per the specified type substitution.

N.B.: The following definition specifies only the default behavior for this method. Specific subclasses are generally expected to override this method.

Overrides:

instantiate in class TypeTerm

eqCode

public final int eqCode()

Description copied from class: Type

Returns a hash code for this type - the reason for using the name eqCode (rather than overriding hashCode), is that it is important to preserve the implementation of java.lang.Object.hashCode for type parameters (to be compatible with ==). All we require with this new code is that it be compatible with type equality as defined by isEqualTo - and it is! Incidentally, the same reason goes for preserving equals for type parameters to be compatible with == - and it is (see TypeParameter).

Overrides:

eqCode in class TypeTerm