Path: csiph.com!aioe.org!news.mb-net.net!open-news-network.org!.POSTED.136.226.197.178.dynamic.wless.zhbmb00p-cgnat.res.cust.swisscom.ch!not-for-mail From: Thomas 'PointedEars' Lahn Newsgroups: comp.lang.javascript Subject: Re: HTML5 embed element event Date: Thu, 21 May 2020 21:50:53 +0200 Organization: PointedEars Software (PES) Lines: 92 Message-ID: <3049967.y3JZ3UGTbG@PointedEars.de> References: <4588804.31r3eYUQgx@PointedEars.de> <510316de-79da-42b4-8502-ce21d07bacdc@googlegroups.com> <12dbcf64-ebca-4c3d-adc7-26ad1246ca63@googlegroups.com> <4261657.LvFx2qVVIh@PointedEars.de> <61275749-9018-4baf-a633-6de74dceedd3@googlegroups.com> Reply-To: Thomas 'PointedEars' Lahn Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 8Bit Injection-Info: gwaiyur.mb-net.net; posting-host="136.226.197.178.dynamic.wless.zhbmb00p-cgnat.res.cust.swisscom.ch:178.197.226.136"; logging-data="8510"; mail-complaints-to="abuse@open-news-network.org" User-Agent: KNode/4.14.10 Cancel-Lock: sha1:CiPBoSRn5wdPurVvSqOoz+Ifg5w= Face: 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 X-User-ID: U2FsdGVkX1++HbScfTC9jUEXOzMosEEHmdWvNyMF35Wf4XtCPDx62A== X-Face: %i>XG-yXR'\"2P/C_aO%~;2o~?g0pPKmbOw^=NT`tprDEf++D.m7"}HW6.#=U:?2GGctkL,f89@H46O$ASoW&?s}.k+&. On Thursday, May 21, 2020 at 11:53:31 AM UTC-5, Thomas 'PointedEars' Lahn > wrote: >> I forgot about Set. I do not know what you mean by “featureNames”, > > Sorry, that was a copy/paste issue from other code I'm working on which > focuses on classes instead of objects. A 'feature' in the context of a > class is a property, a method, or an accessor. This terminology is seen in > compiler work and in some literature such as: > > "Feature-Oriented Programming with Object Algebras" > As I mentioned recently, I have been using the term “feature” in my code for ages[tm] :) >> or why you would pass a reference to a two-element Array. I see now that actually you are NOT doing that. The new meaning of “...” in ECMAScript just has not entered my subconscious yet. For the interested, unaware reader: “...” is not an omission (Perls are warned now), but works *like* an *operator* now (ECMAScript 2015+), such that [...['foo', 'bar'], ...['baz', 'bla']] is now equivalent to ['foo', 'bar', 'baz', 'bla'] which is most useful if ['foo', 'bar'] and ['baz', 'bla'] are return values. Array.prototype.concat(), Array.prototype.push(), and simple uses of Function.prototype.call() and Function.prototype.apply() are thus rendered unnecessary. a.concat('foo', 'bar') → [...a, ...['foo', 'bar']] a.push('foo', 'bar') → a = [...a, ...['foo', 'bar']] o.f.call(o, 'foo', 'bar') → o.f(...['foo', 'bar']) o.f.apply(o, ['foo', 'bar']) → o.f(...['foo', 'bar']) Which means we can also finally write something like var input = '2020-05-21'; new Date(...input.split('-').map((comp, i) => (i == 1 ? comp - 1 : comp))) without a workaround. > The constructor of Set accepts an iterable so you can do: > > new Set([1,2,3]) > > Therefore in a single expression in declarative fashion we can define a > set which contains all of the current property names, and all of the > ancestor property names. To iterate is human, to recurse is divine. I see. Nice line :) > Using the Set approach: > > ``` > let propertyNames = obj => > obj == null ? new Set() : > new Set([ > ...Object.getOwnPropertyNames(obj), > ...featureNames(Object.getPrototypeOf(obj)) That would be ...propertyNames(…) here, I suppose. > ]) > > var el = $0; > > [...propertyNames(el)] IOW, now for simple cases .forEach(…) is rendered unnecessary, too? :-o > .filter(name => name.startsWith('on')) ^^^^^^^^^^ Another "new" feature that had not entered my subconscious yet. > .forEach(name => el[name] = ev => console.log(ev)); For me, a readable code style requires at least braces around both function bodies here, as they are *statements*, not expressions. (If they were more complex expressions, I would put them in parentheses instead; see above.) -- PointedEars FAQ: | | Twitter: @PointedEars2 | Please do not cc me./Bitte keine Kopien per E-Mail.