bug#66756: 30.0.50; [PATCH] Improve discussion of 'let' in Elisp Introduction manual

[Richard Stallman <rms@gnu.org>]

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  > +The @code{let} special form provides a way to confine your variables
  > +to a particular section of your code (in computer science jargon, a
  > +``scope'').  @code{let} creates a name for a @dfn{local variable} that
  > +overshadows any use of the same name outside the @code{let} expression
  > +(we call this ``binding'' the variable).  This prevents any accidental
  > +usage of these variables outside of the @code{let} expression.

This is one of several reasons to use `let'.

Others are

* To compute a value once and use it more than once.

* To create a loop index variable.

* For special variables, to bind them si as to control the behavior
of other code.

Should all of them be mentioned in this node?  I am not sure;
that is a pedagogical question.  But this node shouldn't assert
that one reason is the only reason.


-- 
Dr Richard Stallman (https://stallman.org)
Chief GNUisance of the GNU Project (https://gnu.org)
Founder, Free Software Foundation (https://fsf.org)
Internet Hall-of-Famer (https://internethalloffame.org)