js> (function() { w(yield); }) typein:1: SyntaxError: yield expression must be parenthesized: typein:1: (function() { w(yield); }) typein:1: ................^ js> (function() { w((yield)); }) function () { w((yield)); } js> (function() { w(1 ? yield : 0); }) function () { w(yield); }

Not worth blocking on?

js> (function () { f(x = yield); const x; }) function () { f(yield); const x; }

ES4 is not requiring fully parenthesized yield if the yield expression is the only or last actual parameter. Patch shortly. /be

I'm not in favor of runtime version checking, so these two tests will have to cope -- unless someone feels strongly that those errors should be thrown for version 1.7. A change in non-error semantics would be a different matter. Just relaxing things to permit what was an error before does not motivate me to spend code size and source complexity on version checks. /be

Fixed: js/src/jsparse.c 3.334 /be

verified linux|mac|windows /cvsroot/mozilla/js/tests/js1_8/genexps/regress-384991.js,v <-- regress-384991.js initial revision: 1.1

Having this problem in Firefox 45.0.1. Have it been regressed? Screenshot: http://s18.postimg.org/j8rlroi7t/firefox_yield.png

This is fixed in Firefox 47: bug 1250589.

Thanks for info! One strange thing here is that real error was 'Constructor ... is undefined' which I spotted by Chrome. Once that error was fixed -- yield was gone as well.

Please open a new bug when there is still a problem with Firefox 47 (currently Firefox Developer Edition). Thanks.

I didn't tried in 47. If I will have any problems there, then I will open new one. Thanks.