RE: hooks and let-bound variables

[Drew Adams]

> I find very funny that I only use languages with lexical binding,
> but can still be bitten by it in emacs-lisp.

;-)

Yup.  If you have only lexical binding then you cannot be bitten
by it (or by dynamic binding).

Emacs makes (good) use of dynamic binding, for exactly the kind
of thing you were doing: let-binding around some code whose behavior
you want to change by way of the binding.

In most languages you do not ever want the behavior of existing code
to change at runtime by just changing the value of a global variable
(i.e, from outside that code).  With Common Lisp and Emacs Lisp you
do sometimes want that.

http://www.gnu.org/software/emacs/emacs-paper.html#SEC17