RE: [External] : Re: Passing result of macroexpand-all as argument to a function

[Heime]

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------- Original Message -------
On Thursday, August 10th, 2023 at 9:24 AM, Drew Adams <drew.adams@oracle.com> 
wrote:


> > The usefulness of macroexpand seems to be the ability to output
> > up to a specific expansion level, that's all.
> 
> 
> Two main uses of macro expansion:
> 
> 1. For coders, to debug their macro definitions.
> Expansion lets you see the code you're telling
> the macro to produce.
> 
> 2. For byte-compilation, so for performance.
> As I mentioned the expanded code gets substituted
> for the source macro call, in line. (Nay, its
> byte-compilation gets substituted.)
> 
> For #1 you as a developer call `macroexpand'.
> For #2 code in the byte-compiler calls it (in
> effect).

I think we resolved this whole thing about macros then. 

> > > If you byte-compile the Lisp source code then the
> > > macro call gets macroexpanded during compilation,
> > > and the result of expansion is then compiled to
> > > produce the byte-compiled code. In effect, the
> > > macro-call source code disappears and is replaced
> > > by the expansion, in line, and the resulting code
> > > is then byte-compiled.