Again promises don't shine there. Promises shine when you do something like this
var promise = oauth.get(url); promise.then(...); promise.fail(...); // give promise to end-user and let him attach his own handlers return promise Basically it's an easy way of attaching as many callbacks as you want. Promises are also easier to work with if you want to attach a "successHandler" after the promise has completed. On Fri, Oct 28, 2011 at 12:28 PM, Rob Griffiths <[email protected]> wrote: > @Jake: Do you have any examples of this use-case? When would you reuse a > promise? Currently in jsOAuth I handle success and failures with an API like > > oauth.get(url, successCallback, failureCallback); > > if this was a promise what would it look like? This perhaps? > > var request = oauth.get(url); > request.success(successCallback); > request.failure(failureCallback); > > At which point the code looks more complicated. In other examples I've seen > they do something more like > > var request = oauth.get(url); > request.then(successCallback); > request.cond("failure").then(failureCallback); > > Which looks even more complicated. Maybe an AJAX request is too small of a > piece of work to be using promises for? > > -- > Rob Griffiths > Twitter: @bytespider > Github: https://github.com/bytespider > > bytespider.eu > Sent with Sparrow <http://www.sparrowmailapp.com/?sig> > > On Friday, 28 October 2011 at 12:08, Jake Verbaten wrote: > > Correct, function nesting is a flaw in architecture. > > however promises have their uses because you can pass them back. > > The main use-case for promises for me is that they say "some thing will > happen at some point" and you can listen on that thing multiple times. A > callback is a single callback, it will be invoked once and only once. > > Promises also give you a mechanism of handling errors & success seperately > where as you have to manually do that in callbacks. I think it's just a > pattern / style choice thing. Personally I dont use promises > > On Fri, Oct 28, 2011 at 11:46 AM, Rob Griffiths <[email protected]> wrote: > > @Nick: Thanks for the link, I'll read up and may come back with more > thoughts and questions. > > Is function nesting that much of a problem if you design your architecture > properly? Surely large nests of functions and anonymous functions is just > sloppy coding isn't it? > > -- > Rob Griffiths > Twitter: @bytespider > Github: https://github.com/bytespider > > bytespider.eu > Sent with Sparrow <http://www.sparrowmailapp.com/?sig> > > On Friday, 28 October 2011 at 10:51, Nick Morgan wrote: > > There's a large section in Test-Driven JavaScript Development ( > http://tddjs.com/) about converting a Node app using callbacks to one > using promises. I think a big part of it is just reducing function nesting. > > On 27 October 2011 22:10, bytespider <[email protected]> wrote: > > I've been thibking about promises in javascript, and whilst I think I > understand the basics i fail to see how they are useful over the usual > callback mechanisim. > > I wrote a post http://cl.ly/BMAE to summerise my thoughts and I'd > really like to start a discussion here to talk about the pros and cons > of such methodoligy. > > -- > To view archived discussions from the original JSMentors Mailman list: > http://www.mail-archive.com/[email protected]/ > > To search via a non-Google archive, visit here: > http://www.mail-archive.com/[email protected]/ > > To unsubscribe from this group, send email to > [email protected] > > > > > -- > Nick Morgan > http://skilldrick.co.uk > @skilldrick > > Save our in-boxes! http://emailcharter.org > > -- > To view archived discussions from the original JSMentors Mailman list: > http://www.mail-archive.com/[email protected]/ > > To search via a non-Google archive, visit here: > http://www.mail-archive.com/[email protected]/ > > To unsubscribe from this group, send email to > [email protected] > > > -- > To view archived discussions from the original JSMentors Mailman list: > http://www.mail-archive.com/[email protected]/ > > To search via a non-Google archive, visit here: > http://www.mail-archive.com/[email protected]/ > > To unsubscribe from this group, send email to > [email protected] > > > -- > To view archived discussions from the original JSMentors Mailman list: > http://www.mail-archive.com/[email protected]/ > > To search via a non-Google archive, visit here: > http://www.mail-archive.com/[email protected]/ > > To unsubscribe from this group, send email to > [email protected] > > > -- > To view archived discussions from the original JSMentors Mailman list: > http://www.mail-archive.com/[email protected]/ > > To search via a non-Google archive, visit here: > http://www.mail-archive.com/[email protected]/ > > To unsubscribe from this group, send email to > [email protected] > -- To view archived discussions from the original JSMentors Mailman list: http://www.mail-archive.com/[email protected]/ To search via a non-Google archive, visit here: http://www.mail-archive.com/[email protected]/ To unsubscribe from this group, send email to [email protected]
