> So here are a few questions:
> -> Is lexical scope that important when learning pure functional 
> programming?
> -> Are environments helpful (even the slightest bit) when teaching
> lexical scope?
> -> Where does this idea come from? I have not read a single book, as
> single article nor blog talking about environments.
> -> How can we teach lexical scope? Is there a simple solution, the
> kind of a first year student can understand in less than an hour?

An attempt to answer your question 1.


Bon, c'est en français (sorry French only).

http://www.enseignement.polytechnique.fr/profs/informatique/Luc.Maranget/compil/poly/interprete.html#htoc45



--Luc