Re: Scheme to elisp

[weber <hugows@gmail.com>]

On 16 maio, 12:58, Joost Kremers <joostkrem...@yahoo.com> wrote:
> weber wrote:
> > Or in a simplified form, my problem is : why the snippet below does
> > not work?
>
> [note: the original indentation was confusing:]
>
> > (defun f (n)
> >   (let ((g (lambda (x) (+ 5 x))))
> >     (g (+ n 1))))
>
> > (f 1) -> void-function g
>
> well, elisp is a lisp2, rather than a lisp1 (as scheme is), so a symbol can
> have both a value as a variable *and* a function definition. with let, you
> assign g a value *as a variable*, it does not affect the *function*
> definition of the symbol g.
>
> it is possible to assign an anonymous function as the variable value of a
> symbol. if you do this, you can use either funcall or apply (they have
> different uses) to call the (anonymous) function stored in the variable,
> like this:
>
> (defun f (n)
>   (let ((g (lambda (x) (+ 5 x))))
>     (funcall g (+ n 1))))
>
> alternatively, if you use the common-lisp compatibility package, you can
> use either flet or labels to create function bindings:
>
> (defun f (n)
>   (flet ((g (x) (+ 5 x)))
>     (g (+ n 1))))
>
> note that with flet, you don't use anonymous functions. the syntax is:
>
> (flet ((<function_name> <arg_list> . <function_body>))
>   (<flet_body>)
>   ...)
>
> HTH
>
> --
> Joost Kremers                                      joostkrem...@yahoo.com
> Selbst in die Unterwelt dringt durch Spalten Licht
> EN:SiS(9)

Thank you very much for the explanation...
It did helped!
-weber