Forgot to close that issue. We have docs here: http://www.polymer-project.org/docs/polymer/expressions.html#single-use-bindings
Although, "Expressions" seems like the wrong page for this. Admittedly, all of the data-binding docs need a large overhaul :\ On Tue, Feb 25, 2014 at 11:27 AM, Rafael Weinstein <[email protected]>wrote: > Polymer databinding supports one-time binding. Unfortunatey, this isn't > documented yet (just opened this bug: > https://github.com/Polymer/docs/issues/282), but the basic behavior is: > > -any place you would use a double-mustache {{ foo }} to create a dynamic > binding, you can use double brackets [[ foo ]] to create a one-time > binding. This will not incur the overhead of setting up an observer. > > > On Tue, Feb 25, 2014 at 11:07 AM, Just.A.Guy <[email protected]>wrote: > >> I don't know how polymer does data binding. >> I suspect it is using some time of "onChange" listener. >> >> The more elements that there are to bind increases the overhead of >> supporting the two-way sync process. >> >> I am wondering if there is not some waste in all that monitoring. In my >> experience there are two types >> of data values. >> >> a. Constant - these are set at the time of the instance instantiation and >> do not change during the remaining time of execution. >> b. non-constant - these change when the end user interacts with the >> application. >> >> It seems that polymer only provides support for the type-b variables. >> Yet because of that, as the number of variables >> increases, performance can suffer. If there was a way to identify type-a >> (constants), and then only bind those values >> once (after ready?) without change monitoring, then the amount of >> monitoring for change may have a smaller impact. >> >> Or maybe there is a type-c variable which is only changed by some >> javascript in a callback routine. Then provide >> a function that re-values those changed variables. And have the callback >> script call it after it makes a change. >> That way the only monitored variables would be those that the end user >> can change. >> >> >> Follow Polymer on Google+: plus.google.com/107187849809354688692 >> --- >> You received this message because you are subscribed to the Google Groups >> "Polymer" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to [email protected]. >> To view this discussion on the web visit >> https://groups.google.com/d/msgid/polymer-dev/509d5629-e1be-4b48-8321-283f8a8986fd%40googlegroups.com >> . >> For more options, visit https://groups.google.com/groups/opt_out. >> > > Follow Polymer on Google+: plus.google.com/107187849809354688692 > --- > You received this message because you are subscribed to the Google Groups > "Polymer" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > To view this discussion on the web visit > https://groups.google.com/d/msgid/polymer-dev/CABMdHiQ04razMrGVRnayxZDv36TknCuJpwGTSzQOMcSRqdca-Q%40mail.gmail.com > . > > For more options, visit https://groups.google.com/groups/opt_out. > Follow Polymer on Google+: plus.google.com/107187849809354688692 --- You received this message because you are subscribed to the Google Groups "Polymer" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/polymer-dev/CACGqRCBxwSZ_SX%2BA%2BhzV%3DoEZL4opUsXfBG68ALES0CzaOJ9TRQ%40mail.gmail.com. For more options, visit https://groups.google.com/groups/opt_out.
