On Mon, 2012-01-30 at 02:36 -0600, C Anthony Risinger wrote: > On Mon, Jan 30, 2012 at 1:41 AM, Kees Bos <[email protected]> wrote: > > On Sun, 2012-01-29 at 19:38 -0600, C Anthony Risinger wrote: > >> On Sun, Jan 29, 2012 at 3:23 PM, Peter Bittner <[email protected]> > >> wrote: > >> > Just for curiosity's sake: > >> > > >> >> $wnd.__pygwt_modController.load($pyjs.appname, [ > >> >> 'lib\pyjamas.ui.Panel.js', > >> >> 'lib\pyjamas.ui.HTML.js', > >> >> 'lib\pyjamas.Window.__oldmoz__.js', > >> >> 'lib\pygwt.__oldmoz__.js', > >> >> 'lib\pyjamas.Factory.js', > >> >> 'lib\pyjamas.ui.js', > >> >> 'lib\pyjamas.ui.InnerHTML.js', > >> > > >> > Why do we need dollar signs in JavaScript code? Hmm... > >> > >> `$` is not allowed in python identifiers, thus it guarantees no > >> conflict between the two. unfortunately it's used to protect JS from > >> python (python gets the `$`-less version), and remap tables are used > >> when conflicts arise; i would have done it reverse, where everything > >> python gets the `$`, and that would eliminate the need for remap > >> tables (no native JS objects start with $). > > > > This is historically. The integration between python code and javascript > > used to be very tight. I doubt if that's still needed nowadays. > > could you elaborate [slightly]? do you mean the `$` themselves are > not needed (eg. because of things like dict keys in a special object, > vs. raw JS attribute), or the remap tables, or ... ? doesn't the > translator automatically detect collisions now? i know the `$` is > used all over the place to store temporary JS variables for > implementation of iteration, boolean/typeof, etc, but i don't know if > it's strictly necessary. from a JS() standpoint at least, the > separation is kinder (personally i like knowing if a var is JS/Python > namespace just by convention alone).
In the beginning... python code and javascript code where used together, at least that's what it felt like when I started (somewhere around 0.5). The idea was that you could access javascript variables from python and vice verse (and without prefixes or whatsoever). Since python couldn't have '$' in the variables, these where used in the translator (and a few other places) to create temporary / 'system' variables that shouldn't interfere with possible python code. Later on clashes between javascript python names where fixed by mapping for X to $$X. I'm not sure, but I think the 'from __javascipt__ import X' is introduced later. This deprecates the need for equal python/javascript names. That's for variable/function names. It's different for attribute and method names. There are javascript (DOM) attributes that are called from python. If we would have all python attributes/methods have to start with e.g. '$', all these standard attributes/methods would need an '$' equivalent. That has it's (dis)advantages (speed/argument checking).
