From: Emanuel Berg <incal@dataswamp.org>
To: help-gnu-emacs@gnu.org
Subject: Re: macro that uses local variables
Date: Wed, 09 Aug 2023 23:02:20 +0200 [thread overview]
Message-ID: <87ttt8lyjn.fsf@dataswamp.org> (raw)
In-Reply-To: 2kcpuxgFwdbvgqqotTGBbHttysXpd0MJePuWtRTrxgBSO8PDqktV4MC69COMYE_VgmtspvJoUPAFks7PmHC13rPKjh425adnexzHHReGgWc=@protonmail.com
Heime wrote:
> In the context of a macro, the 'let' command should happen
> outside tho macro quote. With the quote expression in the
> body. Am I right ?
Why do you want to use a macro to begin with?
> (defmacro booster-velocity-change
> (specific-impulse initial-mass final-mass)
> "Compute change of velocity using rocket equation."
>
> (let ( (gravity 9.81) )
> `(* (* ,specific-impulse ,gravity)
> (log (mass-ratio ,initial-mass ,final-mass))) ))
Gets easier with a `defun', and then you can remove all the
complicated quoting as well ...
--
underground experts united
https://dataswamp.org/~incal
prev parent reply other threads:[~2023-08-09 21:02 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-08-08 0:32 macro that uses local variables Heime
2023-08-08 1:27 ` Emanuel Berg
2023-08-09 3:09 ` Heime
2023-08-09 21:02 ` Emanuel Berg [this message]
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