On Wed, Dec 26, 2012 at 2:27 PM, David Herman <[email protected]> wrote: > Well, before I start arguing with you, I'd like to know what argument you're > making. ;-) > > Are you saying we should go back to having a MIME-type (and/or pragma) > opt-in? Your subject line suggests that. Or are you saying we should simply > not support some of the new features in non-strict code? Because your points > only seem to be arguing for the latter, not the former.
Sorry, I'd completely forgotten about those earlier options. I am arguing only the latter. Specifically "Any ES6 features that don't fit into non-strict mode without contortion, including "let" and nested "function", should be available only in strict mode." > > I think the MIME type idea, while obviously attractive for our purposes, > would've had terrible consequences for programmers, and I really hope we > don't have to relitigate that debate. > > Dave > > On Dec 26, 2012, at 2:03 PM, Mark S. Miller <[email protected]> wrote: > >> Hi Brian, thanks for accumulating this data! >> >> Between >> * this data, >> * Apple's decision as recorded at >> <https://bugs.webkit.org/show_bug.cgi?id=27226#c4>, >> * the new function syntax micro-modes, >> * and the "let" issues already discussed, >> I reiterate that we should stop trying to twist the language to >> somehow shoehorn ES6 features into non-strict mode. >> >> For both "function" and "let", when we first discussed trying to >> retrofit sense into ES6 non-strict mode, we knew that this was >> speculative, because non-strict mode cannot include web-breaking >> incompatible changes. This experiment has failed, so we should now >> return to plan A. Any ES6 features that don't fit into non-strict mode >> without contortion, including "let" and nested "function", should be >> available only in strict mode. For new function syntax, if >> shoe-horning it into non-strict mode requires micro-modes as >> previously discussed, then we shouldn't. Whatever the complaints about >> living with one mode distinction, we're certainly not addressing these >> complaints by introducing more mode distinctions. >> >> >> >> On Wed, Dec 26, 2012 at 1:04 PM, Brian Terlson >> <[email protected]> wrote: >>> I have some data on patterns and sites that may break due to the proposed >>> change to semantics of function decls in block scope. I am not advocating >>> for any changes here but merely dumping some data I’ve gathered. I will >>> continue gathering data about this breaking change and potentially others >>> (eg. let[x] = 1), so any further data you folks are interested in let me >>> know. I think the January meeting would be a good venue to discuss any of >>> this in detail if warranted. >>> >>> On December 17th, 2235 sites were crawled and their scripts downloaded. >>> These scripts were then processed in an attempt to identify likely breakages >>> due to the change to the semantics of func decls in block scope. In this >>> dataset, 4% of the scripts contained a function declaration in block scope >>> (mostly inside if and try, although pretty much every node contains a >>> function somewhere in this dataset). However, most of these scripts use the >>> function within the same block and so won’t be broken. 20 sites, however, >>> will likely be broken by this change in some way. There is also a chance >>> that the tool used to identify breakages has missed some code that will >>> breka. >>> >>> >>> >>> Below are some examples of code on the web today that will be broken. For >>> each I include a snippet of code that is heavily edited in an attempt to >>> convey the pattern used and the developer intent. I also attempt to identify >>> what functionality will actually be broken. >>> >>> >>> >>> Most of the breakages occur in non-library code, with two exceptions: qTip >>> 1.0, and thickbox 3. >>> >>> >>> >>> # http://ninemsn.com.au >>> >>> >>> >>> RenderModal = function () { >>> >>> if (x) { // is an array of shortcuts that can be added. Is statically >>> non-empty. >>> >>> function K() { >>> >>> // process the array of shortcuts in some way >>> >>> } >>> >>> } >>> >>> K(); >>> >>> }; >>> >>> >>> >>> ## Scenario >>> >>> >>> >>> 1. Navigate to main page. >>> >>> 2. Click “Add other shortcuts” >>> >>> 3. Click “View more shortcuts” – this will not work. >>> >>> >>> >>> >>> >>> # http://yandex.ru >>> >>> >>> >>> if (_ycssjs("BaH0Fmmo2Sg24lRmTPrK0B8qpaA")) { >>> >>> function cp(g, c, d) { /* ...*/ } >>> >>> >>> >>> function csh_ifgsid(c, b) { /*...*/ } } >>> >>> >>> >>> // ... thousands of lines of code ... >>> >>> >>> >>> >>> >>> if (_ycssjs("rO+QIoSf2L0NwDn6vjJjy+27nxI")) { >>> >>> function news() { >>> >>> csh_if_gsid(); >>> >>> } >>> >>> } >>> >>> >>> >>> if (_ycssjs("YRPF0QVjJmhRiKRu6cvi3YXqYo8")) { >>> >>> // ... bunch of stuff ... >>> >>> cp(); >>> >>> } >>> >>> >>> >>> ## Scenario >>> >>> >>> >>> Unknown >>> >>> >>> >>> >>> >>> # http://g.espncdn.com/nfl-primetime-payoff/en/module/entry?matchupid=478 >>> >>> >>> >>> if (isIE && isWin) { >>> >>> // ... >>> >>> } else { >>> >>> function JSGetSwfVer(i){ >>> >>> // ... >>> >>> } >>> >>> } >>> >>> >>> >>> function checkFlash(myRev) { >>> >>> // ... >>> >>> >>> >>> if (isIE && isWin) { >>> >>> // ... >>> >>> } else { >>> >>> aV = JSGetSwfVer(rV); >>> >>> } >>> >>> >>> >>> } >>> >>> >>> >>> ## Scenario >>> >>> >>> >>> Can’t find a page which uses this code. >>> >>> >>> >>> >>> >>> # http://www.t-online.de >>> >>> >>> >>> if (!Adition_Environment) { >>> >>> var Adition_Environment = (function () { >>> >>> var _this = {}; >>> >>> // ... >>> >>> _this.getPrf = function (cuId) { >>> >>> var prf = ""; >>> >>> try { >>> >>> prf = Adition_Prfstr(cuId); >>> >>> } catch (e) { } >>> >>> return prf; >>> >>> }; >>> >>> // ... >>> >>> })(); >>> >>> } >>> >>> >>> >>> // snip 1k lines >>> >>> if (typeof Adition_Prfstr == "undefined") { >>> >>> function Adition_Prfstr(ADITION_CONTENTUNIT_ID) { >>> >>> // ... >>> >>> } >>> >>> } >>> >>> >>> >>> ## Scenario >>> >>> >>> >>> Required to display advertisements on the page. >>> >>> >>> >>> >>> >>> >>> >>> # http://manormystery.com >>> >>> >>> >>> if (!window._ate) { >>> >>> window._ate = { /* ... */ }; >>> >>> function addthis_open() { /* ... */ } } else { _ate.inst++; } >>> >>> >>> >>> if (_atc.abf) { >>> >>> addthis_open(document.getElementById("ab"), "emailab", >>> window.addthis_url || "[URL]", window.addthis_title || "[TITLE]"); } >>> >>> >>> >>> ## Scenario >>> >>> >>> >>> Social sharing popups broken at least. This may be a general utility used in >>> a number of places. >>> >>> >>> >>> >>> >>> >>> >>> # http://manhunt.net (NSFW, DO NOT VISIT AT WORK) >>> >>> >>> >>> /** @todo isFlashInstalled() should probably be gotten by include from >>> js/cmmn/flashDetect.js or upfunc.js. */ >>> >>> >>> >>> if (typeof isFlashInstalled == 'undefined') { >>> >>> function isFlashInstalled() { >>> >>> var requiredMajorVersion = 6; // Major version of Flash required >>> >>> var requiredMinorVersion = 0; // Minor version of Flash required >>> >>> var requiredRevision = 0; // Minor version of Flash required >>> >>> var s = new SWFObject(); >>> >>> if (!s) return false; >>> >>> var version = s.installedVer; >>> >>> if (!version) return false; >>> >>> return (version.major >= requiredMajorVersion && version.minor >= >>> requiredMinorVersion && version.rev >= requiredRevision); >>> >>> } >>> >>> } >>> >>> isFlashInstalled(); >>> >>> >>> >>> ## Scenario >>> >>> >>> >>> I avoided this site at work for obvious reasons, but it looks like all login >>> functionality will be broken. >>> >>> >>> >>> >>> >>> >>> >>> >>> >>> # http://www.163.com >>> >>> >>> >>> NTESAD_Couplet.prototype = { >>> >>> NTESCreate: function () { >>> >>> >>> >>> var widthsmall = this.options.widthsmall; >>> >>> var width = this.options.width; >>> >>> >>> >>> if (this.options.leftbig != "" && this.options.leftsmall != "") { >>> >>> function bighide() { >>> >>> coupletLeft.style.display = "none"; >>> >>> coupletLeftsmall.style.display = "block"; >>> >>> } >>> >>> >>> >>> function smallhide() { >>> >>> coupletLeftsmall.style.display = "none"; >>> >>> coupletLeft.style.display = "block"; >>> >>> } >>> >>> } >>> >>> >>> >>> if (this.options.rightbig != "" && this.options.rightsmall != "") { >>> >>> function Rbighide() { >>> >>> coupletRight.style.display = "none"; >>> >>> coupletRightsmall.style.display = "block"; >>> >>> } >>> >>> } >>> >>> >>> >>> if (this.NTESPosition()) { >>> >>> if (this.options.leftbig != "" && this.options.leftsmall != "" >>> && this.options.rightbig != "" && this.options.rightsmall != "") { >>> >>> this.NTESBind(coupletclose, "click", function () { >>> bighide(); Rbighide(); coupletRightsmall.style.display = "none"; >>> coupletLeftsmall.style.display = "none"; }); >>> >>> this.NTESBind(coupletclose2, "click", function () { >>> bighide(); Rbighide(); coupletRightsmall.style.display = "none"; >>> coupletLeftsmall.style.display = "none"; }); >>> >>> } >>> >>> } >>> >>> } >>> >>> } >>> >>> >>> >>> ## Scenario >>> >>> >>> >>> Unknown. >>> >>> >>> >>> >>> >>> >>> >>> # http://www22.verizon.com >>> >>> >>> >>> if (floatStyle.match(/Content/)) { >>> >>> var contentDiv = d.getElementById(_b.Preferences.Render.main_content_id >>> || "content"); >>> >>> if (contentDiv == null) { >>> >>> floatStyle = this.Preferences.Render.float_style = 'fixed' >>> >>> } >>> >>> function getRightOfContent() { >>> >>> return contentDiv.offsetWidth + contentDiv.offsetLeft + 1 >>> >>> } >>> >>> function fixBackground() { >>> >>> if (_b.Preferences.Render.fix_background) { >>> >>> db.style.backgroundAttachment = "scroll"; >>> >>> var margin = null; >>> >>> if (document.defaultView && >>> document.defaultView.getComputedStyle) { >>> >>> margin = >>> parseInt(document.defaultView.getComputedStyle(contentDiv, >>> null).getPropertyValue("margin-left"), 10) >>> >>> } else { >>> >>> margin = parseInt(contentDiv.currentStyle.marginLeft, 10) >>> >>> } >>> >>> if (isNaN(margin) || margin == 0) { >>> >>> margin = contentDiv.offsetLeft || 0 >>> >>> } >>> >>> db.style.backgroundPosition = (Math.floor(contentDiv.scrollWidth >>> * -0.5) - 2 + margin) + 'px 0' >>> >>> } >>> >>> } >>> >>> } >>> >>> >>> >>> // getRightOfContent/fixBackground used repeatedly after this. >>> >>> >>> >>> ## Scenario >>> >>> >>> >>> Couldn’t find a scenario where this code was hit, but the site is expansive. >>> Also, the above code is found in at least 2 different scripts across the >>> site. >>> >>> >>> >>> >>> >>> >>> >>> >>> >>> # http://www.jeuxvideo.com >>> >>> >>> >>> if (typeof getAppNexusMegaTag == 'undefined' || typeof getAppNexusMegaTag != >>> 'function') { >>> >>> function getSize1080667() { >>> >>> return '250x250'; >>> >>> } >>> >>> } >>> >>> >>> >>> if (typeof inFIF != "undefined" && inFIF == true) { >>> >>> try { >>> >>> parent.getSize1080667 = getSize1080667; >>> >>> } catch (e) { } >>> >>> } >>> >>> >>> >>> >>> >>> ## Scenario >>> >>> Ad won’t display. >>> >>> >>> >>> >>> >>> >>> >>> # http://msn.foxsports.com >>> >>> /* this function is much faster, so if possible we use it. Some IEs are the >>> only ones I know of that need the idiotic second function, generated by an >>> if clause. */ function add32(a, b) { >>> >>> return (a + b) & 0xFFFFFFFF; >>> >>> } >>> >>> >>> >>> if (md5('hello') != '5d41402abc4b2a76b9719d911017c592') { >>> >>> function add32(x, y) { >>> >>> var lsw = (x & 0xFFFF) + (y & 0xFFFF), >>> >>> msw = (x >> 16) + (y >> 16) + (lsw >> 16); >>> >>> return (msw << 16) | (lsw & 0xFFFF); >>> >>> } >>> >>> } >>> >>> >>> >>> ## Scenario >>> >>> >>> >>> Nothing is necessary broken about this, as long as the first add32 functions >>> properly (today everyone with this code is using the second function). This >>> is a fairly common MD5 library (do a search for “idiotic second function” to >>> get an idea, however this was only found once in the dataset). >>> >>> >>> >>> >>> >>> >>> >>> >>> >>> >>> >>> # http://iwiw.hu/i/belepes >>> >>> >>> >>> (function () { >>> >>> if (jQuery.fn.lazyload) { >>> >>> function a() { >>> >>> return typeof f !== "undefined" ? f : (f = >>> jQuery("body").hasClass("lazyloadimages")) >>> >>> } >>> >>> } >>> >>> jQuery(function () { >>> >>> if (a()) { >>> >>> d.apply(document.body) >>> >>> } >>> >>> }) >>> >>> })(); >>> >>> >>> >>> ## Scenario >>> >>> >>> >>> Unknown >>> >>> >>> >>> >>> >>> >>> >>> >>> >>> # http://www.laposte.net >>> >>> >>> >>> if (!window.$extend) { >>> >>> function $extend(c, a) { >>> >>> for (var b in (a || {})) { >>> >>> c[b] = a[b] >>> >>> } return c >>> >>> } >>> >>> } >>> >>> // $extend used repeatedly after this >>> >>> >>> >>> ## Scenario >>> >>> Unknown >>> >>> >>> >>> >>> >>> >>> >>> # http://atpworldtour.com >>> >>> >>> >>> /* >>> >>> * Stores hash values for localization. >>> >>> * Will need duplicating for each language. >>> >>> */ >>> >>> >>> >>> if (typeof registerNS == "undefined") { >>> >>> function registerNS(ns) { >>> >>> var nsParts = ns.split("."); >>> >>> var root = window; >>> >>> for (var i = 0; i < nsParts.length; i++) { >>> >>> if (typeof root[nsParts[i]] == "undefined") >>> >>> root[nsParts[i]] = new Object(); >>> >>> root = root[nsParts[i]]; >>> >>> } >>> >>> } >>> >>> } >>> >>> >>> >>> registerNS("atp.utilities"); >>> >>> // called repeatedly after this. >>> >>> >>> >>> ## Scenario >>> >>> >>> >>> Entire site is unusable. >>> >>> >>> >>> >>> >>> >>> >>> >>> >>> # http://atwiki.jp >>> >>> >>> >>> if (typeof AddClipsFlag == "undefined") { >>> >>> var AddClipsFlag = 'addclips'; >>> >>> // ... >>> >>> function AddClipsLoad() { /* ... */ } >>> >>> // ... >>> >>> } >>> >>> >>> >>> AddClipsLoad(); >>> >>> >>> >>> ## Scenario >>> >>> >>> >>> RSS functionality broken. This appears to be a library of some kind (see >>> www.addclips.org). >>> >>> >>> >>> >>> >>> >>> >>> # Library: qTip 1.0: >>> https://github.com/Craga89/qTip1/blob/master/1.0.0-rc3/jquery.qtip-1.0.0-rc3.js >>> as seen on Zoompanel.com >>> >>> >>> >>> if (t.options.hide.when.event == "inactive") { >>> >>> function y(z) { >>> >>> >>> >>> } >>> >>> } else { >>> >>> // ... >>> >>> } >>> >>> function x(z) { >>> >>> if (t.options.hide.when.event == "inactive") { >>> >>> y() >>> >>> } >>> >>> } >>> >>> >>> >>> ## Scenario >>> >>> >>> >>> Used on zoompanel.com. Tooltips will never disappear after showing up. >>> >>> >>> >>> >>> >>> # Library: thickbox 3 (http://thickbox.net/), in use on runescape.com and >>> baixaki.com.br if (!(TB_PrevHTML === "")) { >>> >>> function goPrev(){ >>> >>> } >>> >>> $("#TB_prev").click(goPrev); >>> >>> } >>> >>> >>> >>> if (!(TB_NextHTML === "")) { >>> >>> function goNext(){ >>> >>> } >>> >>> $("#TB_next").click(goNext); >>> >>> >>> >>> } >>> >>> >>> >>> document.onkeydown = function (e) { >>> >>> if (keycode == 190) { // display previous image >>> >>> if (!(TB_NextHTML == "")) { >>> >>> document.onkeydown = ""; >>> >>> goNext(); >>> >>> } >>> >>> } else if (keycode == 188) { // display next image >>> >>> if (!(TB_PrevHTML == "")) { >>> >>> document.onkeydown = ""; >>> >>> goPrev(); >>> >>> } >>> >>> } >>> >>> } >>> >>> >>> >>> ## Scenario >>> >>> >>> >>> Going back/forward with keyboard is broken. >>> >>> >>> >>> >>> >>> >>> >>> >>> >>> # http://kankan.com >>> >>> Snippet >>> >>> if (typeof getCookie == 'undefined') { >>> >>> function getCookie(name) { >>> >>> >>> >>> } >>> >>> } >>> >>> >>> >>> // ... >>> >>> >>> >>> if (getCookie('tpar')) { >>> >>> var irStartTime = new Date().getTime(); >>> >>> window.attachEvent('onunload', irTimeStat); } >>> >>> >>> >>> ## Scenario >>> >>> Unknown, possibly just for tracking purposes. >>> >>> >>> >>> >>> >>> # Google +1 library (only seen on TMZ.com, possibly this lib is out of date) >>> try { >>> >>> function h(a) { >>> >>> throw a; >>> >>> } >>> >>> // plus a ton of other decls >>> >>> } catch (e) { } >>> >>> >>> >>> try { >>> >>> h(Error("foo")); >>> >>> // plus a ton of calls to other block scoped functions } catch (e) { } >>> >>> >>> >>> ## Scenario >>> >>> >>> >>> Plus one button is broken. >>> >>> >>> >>> >>> >>> >>> _______________________________________________ >>> es-discuss mailing list >>> [email protected] >>> https://mail.mozilla.org/listinfo/es-discuss >>> >> >> >> >> -- >> Cheers, >> --MarkM >> _______________________________________________ >> es-discuss mailing list >> [email protected] >> https://mail.mozilla.org/listinfo/es-discuss > -- Cheers, --MarkM _______________________________________________ es-discuss mailing list [email protected] https://mail.mozilla.org/listinfo/es-discuss
