Re: printing.el again

[Vinicius Jose Latorre <viniciusjl@ig.com.br>]

Stefan wrote:

>> Maybe this should be documented in Emacs Lisp Reference or in other
>> suitable info, probably Byte Compiler Users Guide. Also other
>> byte-compiler optimizations should be documented.
>
>
> Actually, I don't think optimizations should be particularly mentioned.
> The interesting part of optimizing (featurep 'xemacs) is that it 
> eliminates
> spurious warnings. There are other ways to get the same effect, such as
> what is done with (if (fboundp 'foo) ...) where the test is not optimized
> away, but where warnings are selectively prevented.
>
> I think a chapter on "eliminating warnings" is in order to document 
> the use of
> (featurep 'xemacs), (fboundp 'foo), (defvar foo), (with-no-warning 
> ...), ...


Well, I think it's important to know the optimizations we can use or not 
and when.

Does the byte-compiler try to optimize featurep in general or only the 
pattern (featurep 'xemacs) is optimized?

That is, if I have a code which test (featurep 'some-package) and 
some-package is not loaded, does the byte-compiler eliminate the code 
associated with this test?


Vinicius