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JSObjectOps

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Main Page > SpiderMonkey > JSAPI Reference > JSObjectOps

Defines pointers to custom override methods for a class.

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Warning: JSObjectOps is not a supported API. Details of the API may change from one release to the next. This documentation should be considered SpiderMonkey internals documentation, not API documentation. See bug 408416.

[edit] Syntax 

struct JSObjectOps {
    /* mandatory non-null function pointer members. */
    JSNewObjectMapOp    newObjectMap;
    JSObjectMapOp       destroyObjectMap;
    JSLookupPropOp      lookupProperty;
    JSDefinePropOp      defineProperty;
    JSPropertyIdOp      getProperty;
    JSPropertyIdOp      setProperty;
    JSAttributesOp      getAttributes;
    JSAttributesOp      setAttributes;
    JSPropertyIdOp      deleteProperty;
    JSConvertOp         defaultValue;
    JSNewEnumerateOp    enumerate;
    JSCheckAccessIdOp   checkAccess;

    /* Optionally non-null members. */
    JSObjectOp          thisObject;
    JSPropertyRefOp     dropProperty;
    JSNative            call;
    JSNative            construct;
    JSXDRObjectOp       xdrObject;  /* unused */
    JSHasInstanceOp     hasInstance;
    JSSetObjectSlotOp   setProto;
    JSSetObjectSlotOp   setParent;
    JSTraceOp           trace;
    JSFinalizeOp        clear;
    JSGetRequiredSlotOp getRequiredSlot;
    JSSetRequiredSlotOp setRequiredSlot;
};
Name Type Description
newObjectMap JSNewObjectMapOp Create a JSObjectMap.
destroyObjectMap JSObjectMapOp Destroy a JSObjectMap.
lookupProperty JSLookupPropOp Look up a property, following the prototype chain etc. Implements the main part of JS_LookupProperty.
defineProperty JSDefinePropOp Define a new property on an object. Implements JS_DefineProperty.
getProperty JSPropertyIdOp High-level method to get the value of a property. Implements JS_GetProperty.
setProperty JSPropertyIdOp High-level method to assign to a property. May create a new property. Implements JS_SetProperty.
getAttributes JSAttributesOp Get property attributes. Implements JS_GetPropertyAttributes.
setAttributes JSAttributesOp Set property attributes. Implements JS_SetPropertyAttributes.
deleteProperty JSPropertyIdOp Delete a property.
defaultValue JSConvertOp Convert the given object to a given type.
enumerate JSNewEnumerateOp Enumerate object properties.
checkAccess JSCheckAccessIdOp Custom access control method. Implements JS_CheckAccess.
thisObject JSObjectOp ?
dropProperty JSPropertyRefOp Reference counting method. Release a property obtained via lookupProperty or defineProperty.
call JSNative Call an object as though it were a function.
construct JSNative Constructor.
xdrObject JSXDRObjectOp Reserved. Set this field to NULL.
hasInstance JSHasInstanceOp ?
setProto JSSetObjectSlotOp Set an object's __proto__. Implements JS_SetPrototype.
setParent JSSetObjectSlotOp Set an object's __parent__. Implements JS_SetParent.
trace JSTraceOp ?
clear JSFinalizeOp Remove all the object's own properties. Implements JS_ClearScope.
getRequiredSlot JSGetRequiredSlotOp Get the value of an object slot. Implements JS_GetReservedSlot and others.
setRequiredSlot JSSetRequiredSlotOp Set an object slot. Implements JS_SetReservedSlot and others.

[edit] Description

See JSClass for more information about customizing the behavior of custom objects.

Use JSObjectOps to define an optional structure of pointers to custom property methods for a class. If you define JSObjectOps, you can create methods to override the default methods used by JSClass.

If you create a JSObjectOps structure for a given class, then you must also supply or create methods for creating and destroying the object map used by this object, and you must create custom methods for looking up, defining, getting, setting, and deleting properties. You must also create methods for getting and setting property attributes, checking object access privileges, converting property values, and enumerating properties. All other fields are optional, and if not used, should be set to NULL.

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Retrieved from "http://developer.mozilla.org/en/docs/JSObjectOps"