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Re: Executing part of the code instead of another
From: |
Christopher Dimech |
Subject: |
Re: Executing part of the code instead of another |
Date: |
Wed, 7 Oct 2020 16:05:01 +0200 |
Thank you so very much Tomas. Ok. Got It.
> Sent: Wednesday, October 07, 2020 at 4:01 PM
> From: tomas@tuxteam.de
> To: "Christopher Dimech" <dimech@gmx.com>
> Cc: moasenwood@zoho.eu, help-gnu-emacs@gnu.org
> Subject: Re: Executing part of the code instead of another
>
> On Wed, Oct 07, 2020 at 03:48:51PM +0200, Christopher Dimech wrote:
> > It would be better if you explain to me this progn stuff
> >
> > Have tried an example like this
> >
> > (setq na 8)
> > (setq nb 13)
> > ( if (> nb na)
> > progn (
> > (message "nb > na condition [condition is true]")
> > (message "nb > na condition [condition is true]")
> > )
>
> No. Written in Lisp, it's
>
> (progn
> (thing 1)
> (thing 2)
> ...)
>
> In C (and in conventional maths, you'd write it as you did
> above).
>
> Note that it's the same way as you write (message "foo")
> [you don't write message("foo"), as you'd do in C or
> Python or what not).
>
> Progn is a form to bundle a sequence of forms, which are
> evaluated one after the other. The value of progn is
> that of the last form evaluated (that's the -n), as opposed
> to prog1, which would do the same as progn, but return the
> value of its first form.
>
> Cheers
> - t
>
- Re: Executing part of the code instead of another, (continued)
- Re: Executing part of the code instead of another, Christopher Dimech, 2020/10/07
- Re: Executing part of the code instead of another, Gregory Heytings, 2020/10/07
- Re: Executing part of the code instead of another, Emanuel Berg, 2020/10/07
- Re: Executing part of the code instead of another, Robert Pluim, 2020/10/07
- Re: Executing part of the code instead of another, Emanuel Berg, 2020/10/07
- Re: Executing part of the code instead of another, Robert Pluim, 2020/10/07
- Re: Executing part of the code instead of another, Stefan Monnier, 2020/10/07
- Re: Executing part of the code instead of another, Robert Pluim, 2020/10/07
- Re: Executing part of the code instead of another, Christopher Dimech, 2020/10/07
- Re: Executing part of the code instead of another, tomas, 2020/10/07
- Re: Executing part of the code instead of another,
Christopher Dimech <=
- Re: Executing part of the code instead of another, Leo Butler, 2020/10/08
- RE: Executing part of the code instead of another, Drew Adams, 2020/10/07
- Re: Executing part of the code instead of another, Douglas Lewan, 2020/10/18