Optimize space consumption of environments

[GoogleCodeExporter]

Optimize the memory structure of environments so that they use less heap space.

Currently, token variable environments are represented as scala Lists 
containing Binding elements.

It is possible to reduce space overhead by making each Binding element instead 
contain a pointer to an environment, using the Bindings directly as a linked 
list structure.

This may increase code complexity in multiple places, especially those 
involving closure creation. The reduction in heap usage may not be worth the 
increase in complexity and the potential for errors.

Original issue reported on code.google.com by dkitc...@gmail.com on 16 Nov 2011 at 11:14

[GoogleCodeExporter]

(just cleaning up -- accepting "New" issues)

Original comment by jthywissen on 6 Jul 2012 at 9:58

• Changed state: Accepted