Re: Re: Debug code out of production systems

[liz]

...It addresses all these problems. Very nice!

Thank you for your kind words. But I'm afraid there are still some issues involved ;-(

They alter your source's line numbers...

I've chosen a very simple, line by line algorithm, that will lend itself for rewriting in C if ever necessary. No lines should be removed or added, so line numbers should always be correct (although pod lines that are not activated, are replaced by empty lines). I'm contemplating emptying out lines that start with "#" also, but I'm afraid the additional check (in Perl) would cost more CPU than adding the whole line to the source again and having the Perl parser get rid of such a line (in C).

... These Perl "compilers" do not evaluate source filters at runtime...

Well, add mod_perl to that list. My nice little magic module doesn't do it in mod_perl. ;-( One of the reasons I started this in the first place. ;-(

Anyway, I have added an API for other modules that would allow them to have an arbitrary piece of code stored in a variable to be processed in the same manner. For instance

eval $source;

could become:

ifdef::process( $source ) if exists &ifdef::process;
eval $source;

Now to find out what magic mod_perl is performing when it loads its Perl modules and convince the mod_perl people to add the above extra line... ;-)

Liz

Update:
Actually, I just realized the above could be done smarter:

=begin MODPERL

ifdef::process( $source );

=cut

eval $source;

Under mod_perl, the environment variable MODPERL is always defined and not null. If ifdef is active, then the extra processing line becomes active automatically, making sure the $source will also be processed. If ifdef is not loaded, then the pod section will be skipped, directly evalling the source.