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Groups > comp.lang.lisp > #60931
| From | steve g <Sgonedes1977@gmail.com> |
|---|---|
| Newsgroups | comp.lang.lisp |
| Subject | Re: implementing scheme - implementing macros |
| References | <110hst1$2gjgb$1@dont-email.me> |
| Date | 2026-06-16 21:50 -0400 |
| Message-ID | <87ik7iq6jh.fsf@gmail.com> (permalink) |
Mario Rosell <mario@mariorosell.es> writes:
> [ Repost from Reddit. r/lisp: https://t.ly/Fldzk ]
>
> Hello everyone.
>
> I am making a Scheme R5RS implementation and it is going pretty well.
>
> I am trying implement macros, and don't really know how to implement them.
> Scheme has a pretty complex macro system, so for now I am trying to
> implement defmacro and then implement define-syntax, syntax-case, etc.
>
> Any tips?
using eval is your friend.
the old emacs way was hard to read.
the emacs lisp info page: "
14.1 A Simple Example of a Macro
================================
Suppose we would like to define a Lisp construct to increment a variable
value, much like the ‘++’ operator in C. We would like to write ‘(inc
x)’ and have the effect of ‘(setq x (1+ x))’. Here's a macro definition
that does the job:
(defmacro inc (var)
(list 'setq var (list '1+ var)))
"
you need to ``reevaluate'' the macro twice.
the commmon lisp was uses symbols like @ , . etc..
hope this is helpful.
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implementing scheme - implementing macros Mario Rosell <mario@mariorosell.es> - 2026-06-12 21:15 +0000
Re: implementing scheme - implementing macros steve g <Sgonedes1977@gmail.com> - 2026-06-16 21:50 -0400
Re: implementing scheme - implementing macros Lawrence D’Oliveiro <ldo@nz.invalid> - 2026-06-17 03:14 +0000
Re: implementing scheme - implementing macros Paul Rubin <no.email@nospam.invalid> - 2026-06-16 21:45 -0700
Re: implementing scheme - implementing macros steve g <Sgonedes1977@gmail.com> - 2026-06-19 23:15 -0400
Re: implementing scheme - implementing macros antispam@fricas.org (Waldek Hebisch) - 2026-06-17 14:26 +0000
Re: implementing scheme - implementing macros Kaz Kylheku <046-301-5902@kylheku.com> - 2026-06-23 20:59 +0000
Re: implementing scheme - implementing macros Stefan Monnier <monnier@iro.umontreal.ca> - 2026-06-25 10:59 -0400
Re: implementing scheme - implementing macros Kragen Javier Sitaker <kragen@canonical.org> - 2026-08-29 17:15 -0300
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