Re: lambda inside a let or letrec

[bolega <gnuist006@gmail.com>]

On Jun 9, 10:37 pm, bolega <gnuist...@gmail.com> wrote:
> let me write it more clearly with indents as follows :
>
> (let
> ((a (lambda (n) (+ 1 n)))
>  (b 3))
> (a b))
>
> On Jun 9, 10:34 pm, bolega <gnuist...@gmail.com> wrote:
>
> > My apologies in advance to comp.lang.scheme and comp.lang.lisp.
>
> > I am trying to run a certain syntax inside emacs lisp.
>
> > I know basically how let works
>
> > (let (list of pairs of var value) (function))
>
> > This is like a lambda function call , only the order is different.
>
> > But the novelty i saw reading a book on common lisp or scheme is this
> > and i failed to run in emacs. plz tell what modifications are needed
> > and i know they are different.
>
> > (   (lambda (n) (+ 1 n)) 3)  ;;; works in emacs
>
> > (let
> > ((a (lambda (n) (+ 1 n))) (b 3)) (a b))   ;;; does NOT work in emacs
>
> > basically we are trying to use / abuse the let in that in the pair we
> > define a equal to a lambda. Then another pair where a value of b is
> > defined.
>
> > next, we want a to operate on b.
>
> > Why does it fail ?
>
> > The scheme/lisp book/paper where it was seen (forgot) used letrec.
>
> > Can someone enlighten me how set! and let can be used to formulate
> > recursion when the let has no recursion built in it ?
>
> > thanks a lot.
> > cheers

The following works where I have replaced the association of lambda to
a  _by_  the association of lambda function call to a, ie a numerical
value.

(let
((a ((lambda (n) (+ 1 n)) 5))
 (b 3))
(+ a b))

I am sure I am making some trivial mistake