Class NoObjectType

  • All Implemented Interfaces:
    StaticScope<JSType>, java.io.Serializable
    Direct Known Subclasses:
    NoType

    public class NoObjectType
    extends FunctionType
    The bottom Object type, representing the subclass of all objects. Although JavaScript programmers can't explicitly denote the bottom Object type, it comes up in static analysis. For example, if we have: var x = function() {}; if (x instanceof Array) { f(x); } We need to be able to assign x a type within the f(x) call. It has no possible type, but x would not be legal if f expected a string. So we assign it the NoObjectType.
    See Also:
    Bottom types, Serialized Form
    • Method Detail

      • isSubtype

        public boolean isSubtype​(JSType that)
        Description copied from class: FunctionType
        A function is a subtype of another if their call methods are related via subtyping and this is a subtype of that with regard to the prototype chain.
        Overrides:
        isSubtype in class FunctionType
        Returns:
        this &lt;: that
      • toMaybeFunctionType

        public FunctionType toMaybeFunctionType()
        Description copied from class: JSType
        Downcasts this to a FunctionType, or returns null if this is not a function. For the purposes of this function, we define a MaybeFunctionType as any type in the sub-lattice { x | LEAST_FUNCTION_TYPE <= x <= GREATEST_FUNCTION_TYPE } This definition excludes bottom types like NoType and NoObjectType. This definition is somewhat arbitrary and axiomatic, but this is the definition that makes the most sense for the most callers.
        Overrides:
        toMaybeFunctionType in class FunctionType
      • getImplicitPrototype

        public ObjectType getImplicitPrototype()
        Description copied from class: ObjectType
        Gets the implicit prototype (a.k.a. the [[Prototype]] property).
      • getReferenceName

        public java.lang.String getReferenceName()
        Description copied from class: ObjectType
        Gets the reference name for this object. This includes named types like constructors, prototypes, and enums. It notably does not include literal types like strings and booleans and structural types.
        Returns:
        the object's name or null if this is an anonymous object
      • matchesNumberContext

        public boolean matchesNumberContext()
        Description copied from class: JSType
        This predicate is used to test whether a given type can appear in a numeric context, such as an operand of a multiply operator.
      • matchesObjectContext

        public boolean matchesObjectContext()
        Description copied from class: JSType
        This predicate is used to test whether a given type can appear in an Object context, such as the expression in a with statement. Most types we will encounter, except notably null, have at least the potential for converting to Object. Host defined objects can get peculiar.
      • matchesStringContext

        public boolean matchesStringContext()
        Description copied from class: JSType
        This predicate is used to test whether a given type can appear in a String context, such as an operand of a string concat (+) operator. All types have at least the potential for converting to String. When we add externally defined types, such as a browser OM, we may choose to add types that do not automatically convert to String.
      • removeProperty

        public boolean removeProperty​(java.lang.String name)
        Description copied from class: ObjectType
        Removes the declared or inferred property from this ObjectType.
        Parameters:
        name - the property's name
        Returns:
        true if the property was removed successfully. False if the property did not exist, or could not be removed.
      • setPropertyJSDocInfo

        public void setPropertyJSDocInfo​(java.lang.String propertyName,
                                         JSDocInfo info)
        Description copied from class: ObjectType
        Sets the docInfo for the specified property from the JSDocInfo on its definition.
        info - JSDocInfo for the property definition. May be null.
      • visit

        public <T> T visit​(Visitor<T> visitor)
        Description copied from class: JSType
        Visit this type with the given visitor.
        Overrides:
        visit in class FunctionType
        Returns:
        the value returned by the visitor
        See Also:
        Visitor
      • getConstructor

        public FunctionType getConstructor()
        Description copied from class: ObjectType
        Gets this object's constructor.
        Returns:
        this object's constructor or null if it is a native object (constructed natively v.s. by instantiation of a function)
      • unboxesTo

        public JSType unboxesTo()
        Description copied from class: JSType
        Turn an object type to its corresponding scalar type.
        Overrides:
        unboxesTo in class JSType
        Returns:
        the unboxed type or null if this type does not unbox.
      • hasReferenceName

        public boolean hasReferenceName()
        Description copied from class: ObjectType
        Returns true if the object is named.
        Overrides:
        hasReferenceName in class ObjectType
        Returns:
        true if the object is named, false if it is anonymous
      • isNativeObjectType

        public boolean isNativeObjectType()
        Whether this is a built-in object.
        Overrides:
        isNativeObjectType in class ObjectType
      • getCtorImplementedInterfaces

        public java.lang.Iterable<ObjectType> getCtorImplementedInterfaces()
        Description copied from class: ObjectType
        Gets the interfaces implemented by the ctor associated with this type. Intended to be overridden by subclasses.
        Overrides:
        getCtorImplementedInterfaces in class ObjectType
      • getCtorExtendedInterfaces

        public java.lang.Iterable<ObjectType> getCtorExtendedInterfaces()
        Description copied from class: ObjectType
        Gets the interfaces extended by the interface associated with this type. Intended to be overridden by subclasses.
        Overrides:
        getCtorExtendedInterfaces in class ObjectType
      • matchConstraint

        public void matchConstraint​(JSType constraint)
        Description copied from class: JSType
        Modify this type so that it matches the specified type. This is useful for reverse type-inference, where we want to infer that an object literal matches its constraint (much like how the java compiler does reverse-inference to figure out generics).
        Overrides:
        matchConstraint in class JSType
      • matchRecordTypeConstraint

        public void matchRecordTypeConstraint​(ObjectType constraintObj)