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Re: TCO with named-let via macros

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Richard Smith <null@void.com> writes:

> Axel - I know that elisp doesn't optimise if an expressed recursive
> function is tail-recursive.

actually the byte-compiler does do tail recursive optimizations.

> A practical work-around is an alterative approach using the looping
> built-in's like "dotimes" (?) - where a recursive approach would have
> minimalistic beauty.
> Regards, Rich S


check the elisp manual. it shows how to implement true tail recursion in
emacs.


(defun elisp-sum (args)
  (elisp-sum-aux args 0))

(defun elisp-sum-aux (args res)
  (if (null args)
      res
      (elisp-sum-aux (cdr args) (+ (car args) res))))


you can byte compile it. very simple.

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thanks - calculate pi fn. in elisp Richard Smith <null@void.com> - 2024-07-09 19:48 +0100
  TCO with named-let via macros (was: thanks - calculate pi fn. in elisp) Axel Reichert <mail@axel-reichert.de> - 2024-07-09 23:15 +0200
    Re: TCO with named-let via macros Richard Smith <null@void.com> - 2024-07-10 06:28 +0100
      Re: TCO with named-let via macros steve g <sgonedes1977@gmail.com> - 2024-08-10 15:56 -0400
        Re: TCO with named-let via macros Richard Smith <null@void.com> - 2024-08-10 22:28 +0100
    Re: TCO with named-let via macros Richard Smith <null@void.com> - 2024-07-10 06:36 +0100
      Re: TCO with named-let via macros steve g <sgonedes1977@gmail.com> - 2024-08-10 16:22 -0400
        Re: TCO with named-let via macros Axel Reichert <mail@axel-reichert.de> - 2024-08-10 23:15 +0200
          Re: TCO with named-let via macros steve g <sgonedes1977@gmail.com> - 2024-08-11 14:56 -0400
          Re: TCO with named-let via macros Richard Smith <null@void.com> - 2025-04-08 10:26 +0100
    Re: TCO with named-let via macros Richard Smith <null@void.com> - 2024-07-10 06:59 +0100
    Re: TCO with named-let via macros Richard Smith <null@void.com> - 2024-07-10 09:18 +0100
      Re: TCO with named-let via macros steve g <sgonedes1977@gmail.com> - 2024-08-10 16:26 -0400
        Re: TCO with named-let via macros Richard Smith <null@void.com> - 2024-08-10 22:51 +0100

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