Package com.google.javascript.rhino.jstype

Class NoObjectType

java.lang.Object
com.google.javascript.rhino.jstype.JSType
com.google.javascript.rhino.jstype.ObjectType
com.google.javascript.rhino.jstype.PrototypeObjectType
com.google.javascript.rhino.jstype.FunctionType
com.google.javascript.rhino.jstype.NoObjectType
All Implemented Interfaces:
JSType.WithSourceRef
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:

  • Method Details

    • toMaybeFunctionType

      public final @Nullable 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

    • isNoObjectType

      public boolean isNoObjectType()
      Overrides:
      isNoObjectType in class JSType

    • getImplicitPrototype

      public final @Nullable ObjectType getImplicitPrototype()
      Description copied from class: ObjectType
      Gets the implicit prototype (a.k.a. the [[Prototype]] property).
      Overrides:
      getImplicitPrototype in class PrototypeObjectType

    • getReferenceName

      public 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.

      Returning an empty string means something different than returning null. An empty string may indicate an anonymous constructor, which we treat differently than a literal type without a reference name. e.g. in InstanceObjectType.appendTo(TypeStringBuilder)

      Overrides:
      getReferenceName in class PrototypeObjectType
      Returns:
      the object's name or null if this is an anonymous object

    • matchesNumberContext

      public final 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.
      Overrides:
      matchesNumberContext in class PrototypeObjectType

    • matchesObjectContext

      public final 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.
      Overrides:
      matchesObjectContext in class PrototypeObjectType

    • matchesStringContext

      public final 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.
      Overrides:
      matchesStringContext in class PrototypeObjectType

    • matchesSymbolContext

      public final boolean matchesSymbolContext()
      Description copied from class: JSType
      This predicate is used to test whether a given type can appear in a symbol context such as property access.
      Overrides:
      matchesSymbolContext in class PrototypeObjectType

    • setPropertyJSDocInfo

      public final void setPropertyJSDocInfo(Property.Key propertyName, JSDocInfo info)
      Description copied from class: ObjectType
      Sets the docInfo for the specified property from the JSDocInfo on its definition.
      Overrides:
      setPropertyJSDocInfo in class PrototypeObjectType
      Parameters:
      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:

    • getConstructor

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