diff -r 2050b3a0aadc -r d8e365854b3c nashorn/samples/this_for_eval.js --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/nashorn/samples/this_for_eval.js Fri Sep 04 17:11:06 2015 +0530 @@ -0,0 +1,54 @@ +/* + * Copyright (c) 2015, Oracle and/or its affiliates. All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * + * - Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * + * - 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. + * + * - Neither the name of Oracle nor the names of its + * contributors may be used to endorse or promote products derived + * from this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "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 THE COPYRIGHT OWNER 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. + */ + +// how to pass arbitrary "this" object for eval'ed script? + +var obj = { foo: 44 }; + +// the following won't work. eval.apply is indirect eval call +// and so 'this' will be global object always! So, this +// line will print 'undefined' +eval.apply(obj, [ " print(this.foo)" ]); + +obj.myEval = eval; + +// still won't work - still indirect 'eval' call! +// still undefined is printed! +obj.myEval("print(this.foo)"); + +function func(code) { + eval(code); +} + +// eval called inside func and so get's func's "this" as it's "this"! +// So, 44 is printed + +func.apply(obj, [ "print(this.foo)" ]);