Augmenting Types
in [JavaScript]
|
From: John G Harris on 3 Jan 2010 12:51 On Sun, 3 Jan 2010 at 08:38:18, in comp.lang.javascript, Dmitry A. Soshnikov wrote: >On 3 0 <snip> >> terrible idea >> terrible >> terrible idea > >Please, don't use demagogy, propaganda, and <snip> Please don't give such misleading quotes. They are a form of demagogy and propaganda. You could have quoted like this : >> In a Web page, it's generally a terrible idea <your complaint about 'terrible'> >>as scripts typically >> have to co-exist with others. <your agreement about 'co-exist'> John -- John Harris
From: Dmitry A. Soshnikov on 3 Jan 2010 13:18 On 3 Ñнв, 20:51, John G Harris <j...(a)nospam.demon.co.uk> wrote: > On Sun, 3 Jan 2010 at 08:38:18, in comp.lang.javascript, Dmitry A.Soshnikov wrote: > >On 3 0 >  <snip> > >> terrible idea > >> terrible > >> terrible idea > > >Please, don't use demagogy, propaganda, and > >  <snip> > > Please don't give such misleading quotes. They are a form of demagogy > and propaganda. > Please, pay attention that I used it specially (as a kind of irony) to show, how it looks. For what reason, I should give in on provocation and accept such rules when one person statements his humble opinion with sure tone "That's wrong. That's terrible." (this person tries to take the main role and to take the dialog in his hands) and the other one should prove why it's not so (this person is kind of that justifies). It's direct demagogy which I see and don't wanna accept. That's it. Objections? > You could have quoted like this : > > >> In a Web page, it's generally a terrible idea > >  <your complaint about 'terrible'> > I know that, thanks. > >>as scripts typically > >> have to co-exist with others. > >  <your agreement about 'co-exist'> > I also know that, thanks. /ds
From: Jorge on 3 Jan 2010 13:50 On Jan 3, 6:51 pm, John G Harris <j...(a)nospam.demon.co.uk> wrote: > (...) > >> as scripts typically > >> have to co-exist with others. > > <your agreement about 'co-exist'> "agreement" ? The typicality of that hypothetical coexistence is very debatable. And, in any case, "others" is !== "unknown scripts". Do you allow "unknown" code to run in your page ? Does any of these -hypothetical- cohabitant scripts break anything ? And if they do, why ? Don't their authors know about .hasOwnProperty() existence and purpose ? Is that reason enough to ditch .prototype inheritance altogether ? The answer, in general, is NOT yes. The answer, in general, is of course NOT. -- Jorge.
From: David Mark on 3 Jan 2010 18:21 On Jan 3, 1:50 pm, Jorge <jo...(a)jorgechamorro.com> wrote: > On Jan 3, 6:51 pm, John G Harris <j...(a)nospam.demon.co.uk> wrote: > > > (...) > > >> as scripts typically > > >> have to co-exist with others. > > > <your agreement about 'co-exist'> > > "agreement" ? > > The typicality of that hypothetical coexistence is very debatable. That's ludicrous. How many Web pages use a single script from a single author (well, I know of a few at least). :) > And, in any case, "others" is !== "unknown scripts". Do you allow > "unknown" code to run in your page ? Me? Not typically, no. Am I typical? > Does any of these -hypothetical- > cohabitant scripts break anything ? You are babbling. > And if they do, why ? Don't their > authors know about .hasOwnProperty() existence and purpose ? You truly are a student of Crockford. For about the millionth time, that method doesn't work in "ancient" browsers like Safari 2. I see it used without proper feature detection and wonder if the authors realize their scripts will suddenly halt at that spot. Does that seem a sound degradation strategy to you? And of all the miserable JS libraries out there, how many actually filter for-in loops in any form? > Is that > reason enough to ditch .prototype inheritance altogether ? Does it seem to you that I've "ditched" ".prototype inheritance". Look again. > The answer, > in general, is NOT yes. > The answer, in general, is of course NOT. Lucid as always. :)
From: JR on 3 Jan 2010 19:18
On Jan 3, 3:40 am, Ryan Chan <ryanchan...(a)gmail.com> wrote: > Have read Douglas Crockfore's JavaScript The Good Parts, it recommend > Augmenting Types, e.g. > > Function.prototype.method = function(name, func) { > this.prototype[name] = func; > return this; > > }; I've read the book too, but in my version (2008 in Portuguese) that function is slightly different, with one very important feature test: Function.prototype.method = function (name, func) { if (!this.prototype[name]) { this.prototype[name] = func; // I didn't see this return this mentioned above. } }; And there is a precautionary note about augmenting types, specially when the page utilizes different libraries / codes. I also have not read Douglas recommending this type of thing, but saying that it was possible to do so, arguing that it could make improvements in the expressiveness of JavaScript. However, I must admit that that 'part' of the book is confusing and can mislead readers about the matter (augmenting types); in other words, a reader might unwittingly adopt the book's example as a good practice, what would be a temerity. > String.method('trim', function() { > return this.replace(/^\s+|\s+$/g, ''); > > }); > > Is this a good thing in your opinion? No, it isn't, even in case you know exactly what you're doing. -- JR |