/* * 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 <JavaScriptCore/JavaScriptCore.h> #if JSC_OBJC_API_ENABLED /*! @protocol @abstract JSExport provides a declarative way to export Objective-C objects and classes -- including properties, instance methods, class methods, and initializers -- to JavaScript. @discussion When an Objective-C object is exported to JavaScript, a JavaScript wrapper object is created. In JavaScript, inheritance works via a chain of prototype objects. For each Objective-C class in each JSContext, an object appropriate for use as a prototype will be provided. For the class NSObject the prototype will be the Object prototype. For all other Objective-C classes a prototype will be created. The prototype for a given Objective-C class will have its internal [Prototype] property set to point to the prototype created for 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. JavaScriptCore also produces a constructor for each Objective-C class. The constructor has a property named 'prototype' that references the prototype, and the prototype has a property named 'constructor' that references the constructor. By default JavaScriptCore does not export any methods or properties from an Objective-C class to JavaScript; however methods and properties may be exported explicitly using JSExport. For each protocol that a class conforms to, if the protocol incorporates the protocol JSExport, JavaScriptCore exports the methods and properties in that protocol to JavaScript For each exported instance method JavaScriptCore will assign a corresponding JavaScript function to the prototype. For each exported Objective-C property JavaScriptCore will assign a corresponding JavaScript accessor to the prototype. For each exported class method JavaScriptCore will assign a corresponding JavaScript function to the constructor. For example: <pre> @textblock @protocol MyClassJavaScriptMethods <JSExport> - (void)foo; @end @interface MyClass : NSObject <MyClassJavaScriptMethods> - (void)foo; - (void)bar; @end @/textblock </pre> Data properties that are created on the prototype or constructor objects have the attributes: <code>writable:true</code>, <code>enumerable:false</code>, <code>configurable:true</code>. Accessor properties have the attributes: <code>enumerable:false</code> and <code>configurable:true</code>. If an instance of <code>MyClass</code> is converted to a JavaScript value, the resulting wrapper object will (via its prototype) export the method <code>foo</code> to JavaScript, since the class conforms to the <code>MyClassJavaScriptMethods</code> protocol, and this protocol incorporates <code>JSExport</code>. <code>bar</code> will not be exported. JSExport supports properties, arguments, and return values of the following types: Primitive numbers: signed values up to 32-bits convert using JSValue's valueWithInt32/toInt32. Unsigned values up to 32-bits convert using JSValue's valueWithUInt32/toUInt32. All other numeric values convert using JSValue's valueWithDouble/toDouble. BOOL: values convert using JSValue's valueWithBool/toBool. id: values convert using JSValue's valueWithObject/toObject. Objective-C instance pointers: Pointers convert using JSValue's valueWithObjectOfClass/toObject. C structs: C structs for CGPoint, NSRange, CGRect, and CGSize convert using JSValue's appropriate methods. Other C structs are not supported. Blocks: Blocks convert using JSValue's valueWithObject/toObject. All objects that conform to JSExport convert to JavaScript wrapper objects, even if they subclass classes that would otherwise behave differently. For example, if a subclass of NSString conforms to JSExport, it converts to JavaScript as a wrapper object rather than a JavaScript string. */ @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 <code>doFoo:withBar:</code> will be exported as <code>doFooWithBar</code>. The default conversion may be overriden using the JSExportAs macro, for example to export a method <code>doFoo:withBar:</code> as <code>doFoo</code>: <pre> @textblock @protocol MyClassJavaScriptMethods <JSExport> JSExportAs(doFoo, - (void)doFoo:(id)foo withBar:(id)bar ); @end @/textblock </pre> 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