mustache i18n support in django

a.js

var mus = require('mustache');

var t = npgettext("abcadfadf a", "%(count)d app", "%(count)d apps", count);

function gettext_plural() {
    return function(text, render) {
        try {
            var ctx = JSON.parse(text);
            var count = parseInt(render(ctx[0]), 10);
            return render(count > 1 && ctx[2] ? ctx[2] : ctx[1]);
        } catch (ex) {
            return '';
        }
    }
}

(function() {
  var oldMake = mus.Context.make;
  var Context = mus.Context;
  var ctx = new Context({gettext_plural: gettext_plural});
  Context.make = function(view) {
    return (view instanceof Context) ? view : new Context(view, ctx);
  };
})();

/*
=> tmpl
{{# _ }}{{app_num}} App{{ plural "{{app_num}}" }}{{app_num}} Apps{{/_}}


=> parse_result
-> count_id
-> text
-> text_plural

=> output
'[[#gettext_plural]]%s[[/gettext_plural]]' %
json_encode([
    count_id,
    translation.ungettext(text, text_plural, 1),
    translation.ungettext(text, text_plural, 2)
])



*/

console.log(
    mus.render(
        '{{#apps}} * {{#gettext_plural}}["{{app_num}}", "{{app_num}} App", "{{app_num}} Apps"]{{/gettext_plural}}\n{{/apps}}',
        { apps: [{app_num: 4}, {app_num: 1}] }
    ),

    mus.render(
        '{{#gettext_plural}}["{{app_num}}", "{{app_num}} App", "{{app_num}} Apps"]{{/gettext_plural}}\n',
        {app_num: 4}
    ),

    mus.render(
        '{{#gettext_plural}}["{{app_num}}", "{{app_num}} App", "{{app_num}} Apps"]{{/gettext_plural}}\n',
        {app_num: 1}
    )
);

b.py

import re

con_re = re.compile(r'\{\{#(plural|count|context)#\}\}')

def get(txt):
    ctx = con_re.split(txt)
    ret = dict(msg=ctx.pop(0))
    ret['single'] = ret['msg']

    if not ctx:
        return ret

    for idx in range(0, len(ctx), 2):
        ret[ctx[idx]] = ctx[idx + 1]

    return ret


print get('''{{count}} app.{{#plural#}}{{count}} apps.{{#count#}}{{count}}''')

print get('''{{count}} app.''')