Re: Can't compile

[Kevin Rodgers <kevin.d.rodgers@gmail.com>]

Robert Thorpe wrote:
> On Feb 24, 10:28 am, Xavier Maillard <z...@gnu.org> wrote:
>> Hi,
>>
>> I am trying to byte-compile nero.el[1] but it just fails with
>> this error:
>>
>> In nero-restore-match:
>> nero.el:1526:17:Warning: `string-to-int' is an obsolete function (as of Emacs
>>     22.1); use `string-to-number' instead.
>> nero.el:2119:1:Error: Symbol's function definition is void: nero-follow-numbers
>> make: *** [nero.elc] Error 1
>>
>> The first warning is easy to fix (and I fixed it) but what about
>> the second error ?
> 
> I don't know anything about this code, but what is shown here is a
> rather common lisp error.
> 
> The function nero-follow-numbers is used in a macro.  This macro is
> used in the file/compilation block nero.elc.
> The bytecompiler works on a per file basis.  It compiles each of the
> defuns to bytecodes completing it's actions once the file is
> finished.  Macros though must be expanded when the code is being read,
> at this stage the defuns in the file have not yet been finalised.
> 
> This works fine for the normal evalutator because it finalises and
> installs a function at the end of the defun form.
> 
> This is why "eval-and-compile" is needed.

A cleaner design would be for the macro to return a form that contains a
call to the function, rather calling the function during macro expansion
to generate the returned form.

-- 
Kevin Rodgers
Denver, Colorado, USA