Symfony asset version handling for Assetic

Translated to the symfony use-case:

Bundle X could specify jQuery 1 (i.e. load the latest version)
Bundle Y could specify jQuery 1.5
Bundle Z could specify jQuery 1.4

X and Y could be enabled
X and Z potentially could (a request for the latest version doesn't mean an old one won't work)
Y and Z cannot be enabled at the same time

If someone tried to enable bundles Y and Z, Assetic could display a warning.

Q: Should bundles be this autonomous, or should users have to include the JS/CSS assets themselves?

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From the Google documentation about their approach (http://code.google.com/apis/libraries/devguide.html):


google.load gives you two ways to specify which version of the library you wish to load. You can request:
A specific version (such as google.load("jqueryui", "1.8.2");, which loads that exact version of the library (in this case, version 1.8.2).
A truncated version (such as google.load("jqueryui", "1");, which loads the most recent version in that branch (in this case, 1.8.2).

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