[plt-scheme] Closures

Matthias Felleisen wrote:
> BUT, neither environments nor closures are a necessity for executing 
> programs that deal with functions as ordinary values. The history of 
> computing has proposed a number of mechanisms and for all we know, we 
> chose the wrong one.

And this mechanisms are? (I'll do my homework gooogle search but some 
starting points are critical for this) :)

-- 
regards,
Jakub Piotr Cłapa