wytp.types.util

Class StdTypeEnvironment

java.lang.Object

wytp.types.util.StdTypeEnvironment

All Implemented Interfaces:

TypeInferer.Environment

public class StdTypeEnvironment
extends Object
implements TypeInferer.Environment

Provides a very simple typing environment which defaults to using the declared type for a variable (this is the "null" case). However, the environment can also be updated to override the declared type with a new type as appropriate.

Author:

David J. Pearce

Constructor Summary

Constructors

Constructor and Description
StdTypeEnvironment()
StdTypeEnvironment(Map<WyalFile.VariableDeclaration,WyalFile.Type> refinements)

Method Summary

Modifier and Type	Method and Description
Set<WyalFile.VariableDeclaration>	getRefinedVariables()
WyalFile.Type	getType(WyalFile.VariableDeclaration var) Return the current type associated with a given variable.
TypeInferer.Environment	refineType(WyalFile.VariableDeclaration var, WyalFile.Type refinement) Refine the type associated with a given variable declaration in this environment, which produces a completely new environment containing the refined type.
String	toString()

Methods inherited from class java.lang.Object

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

Constructor Detail

StdTypeEnvironment

public StdTypeEnvironment()

StdTypeEnvironment

public StdTypeEnvironment(Map<WyalFile.VariableDeclaration,WyalFile.Type> refinements)

Method Detail

getType

public WyalFile.Type getType(WyalFile.VariableDeclaration var)

Description copied from interface: TypeInferer.Environment

Return the current type associated with a given variable. It is generally assumed that this either matches its declared type, or is a refinement thereof.

Specified by:

getType in interface TypeInferer.Environment

Returns:

refineType

public TypeInferer.Environment refineType(WyalFile.VariableDeclaration var,
                                          WyalFile.Type refinement)

Description copied from interface: TypeInferer.Environment

Refine the type associated with a given variable declaration in this environment, which produces a completely new environment containing the refined type. Observe that the variable need not have been previously declared for this to make sense. Also, observe that the resulting type for a given variable is the intersection of its original type and the refined type.

Specified by:

refineType in interface TypeInferer.Environment

Returns:

getRefinedVariables

public Set<WyalFile.VariableDeclaration> getRefinedVariables()

Specified by:

getRefinedVariables in interface TypeInferer.Environment

toString

public String toString()

Overrides:

toString in class Object