Error-free deep property access?
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From: Thomas 'PointedEars' Lahn on 11 May 2010 17:13 Garrett Smith wrote: > Asen Bozhilov wrote: >> eval(properties); >> >> Of course that is not solve the design problems. I will prefer to use >> array which contain each property name. For example: >> >> deep(context, ['property1', 'property2', 'propertyN']); > > Does deep check own or prototype? You want to re-read the thread and re-think your question. PointedEars -- Danny Goodman's books are out of date and teach practices that are positively harmful for cross-browser scripting. -- Richard Cornford, cljs, <cife6q$253$1$8300dec7(a)news.demon.co.uk> (2004)
From: Scott Sauyet on 11 May 2010 17:20 Matt Kruse wrote: > On May 11, 2:45 pm, Asen Bozhilov <asen.bozhi...(a)gmail.com> wrote: >> I will prefer to use >> array which contain each property name. For example: >> deep(context, ['property1', 'property2', 'propertyN']); > > How is that any better than joining the array with "." and passing a > single string?! It's more general, not necessarily better. But it does address the issues Thomas raises, and allows for the generality I was suggesting. If your simple cases are all you ever need, by all means use a simpler strategy. It also has the advantage that you can pass variables holding strings without manual concatenation. The only thing I would do differently than the above is that I would remove the array and deal with variable arguments; this seems cleaner to me: deep(context, 'property1', 'property2', 'propertyN'); This still does not get at the even more general solution I mentioned, and which I tried to implement some time ago. But of course that solution had the problem yours does with property names containing periods or brackets. I used an escape syntax for those, and that's where some of the clean API went up in smoke. I will see if I still have a copy of that code at home. I'm curious to see how much five-year-old code might make me shudder. -- Scott
From: Asen Bozhilov on 11 May 2010 17:24 Matt Kruse wrote: > Asen Bozhilov wrote: > > I will prefer to use > > array which contain each property name. For example: > > deep(context, ['property1', 'property2', 'propertyN']); > > How is that any better than joining the array with "." and passing a > single string?! At all you miss the point and wrote in arrogant way that reply. Could you show an implementation which works with: var obj = { property : { '.property.' : { '[property]' : true } } }; $prop(obj, 'property[.property.][[property]]'); I expect `true' instead of `undefined'. So when you show that implementation we can again talk about the complex of the problem which you try to solve.
From: Matt Kruse on 11 May 2010 17:28 On May 11, 4:20 pm, Scott Sauyet <scott.sau...(a)gmail.com> wrote: > this seems cleaner to me: > deep(context, 'property1', 'property2', 'propertyN'); Would it handle this: deep(context, 'prop1[0]') if 'context' has no property named 'prop1'? And what if 'context' has a property named 'myarray[0]' which is an array? deep(context, 'myarray[0][0]') ? Matt Kruse
From: Garrett Smith on 11 May 2010 17:30
Matt Kruse wrote: > On May 11, 2:45 pm, Asen Bozhilov <asen.bozhi...(a)gmail.com> wrote: >> Square bracket notation allow to used returned result by expression, >> and that result is not bound as Identifiers rules defined by ECMA-262. >> With your strategy you would have problems. For example: >> var obj = {}; >> obj['.prop.'] = true; >> obj['[prop]'] = true; >> >> print(obj['.prop.']); >> print(obj['[prop]']) >> >> Your strategy is too complex > > But why would you EVER do that? I'm not building this for idiots! > Host: navigator.plugins["Shockwave Flash 2.0"]? User defined: myObject[ prop.toString() ] = val; [...] -- Garrett comp.lang.javascript FAQ: http://jibbering.com/faq/ |