Re: Macro vs Function

[Herbert Euler]

> From: "Stuart D. Herring" <address@hidden>
> Reply-To: address@hidden
> To: "Herbert Euler" <address@hidden>
> CC: address@hidden
> Subject: Re: Macro vs Function
> Date: Wed, 12 Apr 2006 08:26:05 -0700 (PDT)
>
> This much you can solve simply by using ',(car largs).  In general, in a `:
>
> x              "use literally and eval later"
> 'x             "never eval at all"
> ,x             "use symbolically and eval later"
> (eval x)       "use literally and eval twice later"
> ,(eval x)      "evaluate now and later"
> ',(eval x)     "evaluate now only"
> ',x            "use symbolically and don't eval later"
>
> (...where 'now' is macro expansion time and 'later' is interpretation
> time.)  You want the last one, since largs is a macro argument (use
> symbolically) but you don't want the resulting list evaluated.  (I hope I
> got all those meanings right!)

Oh yes!  I'm still a bit confused by the time when I wrote that definition.
Yes, ',x => (quote (\, x)) is what I need.

Regards,
Guanpeng Xu

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