Generic Bundling

Jorge Chamorro jorge at
Mon Oct 14 07:57:45 PDT 2013

On 13/10/2013, at 21:34, Brendan Eich wrote:
> Jorge Chamorro wrote:
>> Are main.js and two separate files, or is main.js expected to come from into
> The latter.
>>  I think the latter would be best because it would guarantee that the assets are there by the time main.js runs, as if they were local files, ready to be require()d synchronously.
> How would old browsers cope, though? They would load only lib/main.js (and possibly make a request storm, as Russell brought out elsewhere in this thread), so (synchronous) require of another member of might or might not work.


The only 'fix' that I can think of is to use sync XHRs (I know, I know...). For example this code would run fine in any browser, with or without .zip packages:

function require (modulo) {
  if (!require.modulos) {
    require.modulos= Object.create(null);
  if (!(modulo in require.modulos)) {
    var xhr= new XMLHttpRequest();'GET', modulo, false);
    require.modulos[modulo]= Function('require', xhr.responseText)(require);
  return require.modulos[modulo];


Only much slower in old browsers, but lightning fast with .zip packages (if you choose wisely what you put into the .zip package).

> A prefetching <link> element might not suffice in old browsers, I'm pretty sure it won't.
> If the only way to cope with downrev browsers is to use Traceur, so be it. We just need to be sure we're not missing some clever alternative.

I for one don't have any better ideas, sorry.

Thank you,
( Jorge )();

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