/* * Copyright (C) 2013 Apple Inc. All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */ #import #if JSC_OBJC_API_ENABLED /*! @protocol @abstract JSExport provides a declarative way to export Objective-C instance methods, class methods, and properties to JavaScript code. @discussion When a JavaScript value is created from an instance of an Objective-C class for which no copying conversion is specified a JavaScript wrapper object will be created. In JavaScript, inheritance is supported via a chain of prototype objects, and for each Objective-C class (and per JSContext) an object appropriate for use as a prototype will be provided. For the class NSObject the prototype object will be the JavaScript context's Object Prototype. For all other Objective-C classes a Prototype object will be created. The Prototype object for a given Objective-C class will have its internal [Prototype] property set to point to the Prototype object of the Objective-C class's superclass. As such the prototype chain for a JavaScript wrapper object will reflect the wrapped Objective-C type's inheritance hierarchy. In addition to the Prototype object a JavaScript Constructor object will also be produced for each Objective-C class. The Constructor object has a property named 'prototype' that references the Prototype object, and the Prototype object has a property named 'constructor' that references the Constructor. The Constructor object is not callable. By default no methods or properties of the Objective-C class will be exposed to JavaScript; however methods and properties may explicitly be exported. For each protocol that a class conforms to, if the protocol incorporates the protocol JSExport, then the protocol will be interpreted as a list of methods and properties to be exported to JavaScript. For each instance method being exported a corresponding JavaScript function will be assigned as a property of the Prototype object. For each Objective-C property being exported a JavaScript accessor property will be created on the Prototype. For each class method exported a JavaScript function will be created on the Constructor object. For example:

@textblock
    @protocol MyClassJavaScriptMethods 
    - (void)foo;
    @end

    @interface MyClass : NSObject 
    - (void)foo;
    - (void)bar;
    @end
@/textblock

Data properties that are created on the prototype or constructor objects have the attributes: writable:true, enumerable:false, configurable:true. Accessor properties have the attributes: enumerable:false and configurable:true. If an instance of MyClass is converted to a JavaScript value, the resulting wrapper object will (via its prototype) export the method foo to JavaScript, since the class conforms to the MyClassJavaScriptMethods protocol, and this protocol incorporates JSExport. bar will not be exported. Properties, arguments, and return values of the following types are supported: Primitive numbers: signed values of up to 32-bits are converted in a manner consistent with valueWithInt32/toInt32, unsigned values of up to 32-bits are converted in a manner consistent with valueWithUInt32/toUInt32, all other numeric values are converted consistently with valueWithDouble/ toDouble. BOOL: values are converted consistently with valueWithBool/toBool. id: values are converted consistently with valueWithObject/toObject. Objective-C Class: - where the type is a pointer to a specified Objective-C class, conversion is consistent with valueWithObjectOfClass/toObject. struct types: C struct types are supported, where JSValue provides support for the given type. Support is built in for CGPoint, NSRange, CGRect, and CGSize. block types: Blocks can only be passed if they had been converted successfully by valueWithObject/toObject previously. For any interface that conforms to JSExport the normal copying conversion for built in types will be inhibited - so, for example, if an instance that derives from NSString but conforms to JSExport is passed to valueWithObject: then a wrapper object for the Objective-C object will be returned rather than a JavaScript string primitive. */ @protocol JSExport @end /*! @define @abstract Rename a selector when it's exported to JavaScript. @discussion When a selector that takes one or more arguments is converted to a JavaScript property name, by default a property name will be generated by performing the following conversion: - All colons are removed from the selector - Any lowercase letter that had followed a colon will be capitalized. Under the default conversion a selector doFoo:withBar: will be exported as doFooWithBar. The default conversion may be overriden using the JSExportAs macro, for example to export a method doFoo:withBar: as doFoo:

@textblock
    @protocol MyClassJavaScriptMethods 
    JSExportAs(doFoo,
    - (void)doFoo:(id)foo withBar:(id)bar
    );
    @end
@/textblock

Note that the JSExport macro may only be applied to a selector that takes one or more argument. */ #define JSExportAs(PropertyName, Selector) \ @optional Selector __JS_EXPORT_AS__##PropertyName:(id)argument; @required Selector #endif