On Tue, Mar 13, 2012 at 8:15 AM, Jason Orendorff <[email protected]> wrote: > Kevin Smith wrote: >> For the surveyed code, >> the percentage of function expressions which do not reference "this" ranges >> between 31% and 87%. About half of all function expressions are suitable >> for conversion to BTFs. Clearly BTFs would offer immediate quantifiable >> benefit.
I'm confused by this paragraph. Functions that benefit from 'this' binding would reference 'this' or an alias for 'this' right? ... > This is great data to have. > > Something I found really interesting about this is that if you delete > Facebook and Netflix, this number goes up to 27%. In the MooTools > code, it's 40%. So either it just varies wildly depending on > programming style, or else library code has a greater need for > "expression functions" than application code. Everyone has to deal with the this-binding problem; every project will have some strategy. So a better analysis would start by determining the strategy for each project, then using the counting analysis to determine the ratio of functions needing this-binding based on the strategy. I think you will come up with a much higher number. Some of the this-binding strategies I know about: var self = this; // usually 'self' but certainly 'this' alone on ther RHS Prototype bind http://www.prototypejs.org/api/function/bind local library bind/bindFixed (eg Firebug source) function() {}.bind(this); // modern code jjb _______________________________________________ es-discuss mailing list [email protected] https://mail.mozilla.org/listinfo/es-discuss
