[Edited Its wrong of me to characterize everything done by a particular author this way. There are a small set of examples of bugs in his published work and some things like years passing while bug fixes submitted to rt.cpan.org aren't applied.] Ingy is no example. Bugs in his work are unsurprising and regular. I don't know whether this is related to his use of source filters or not.

I checked Damian's list of categorized modules for stuff that used something from Filter. Here's how it breaks down for his source filtering modules. It works out that while Damian has written several things using source filters, he has only one thing that isn't marked experimental that actually uses source filters that would be available in production. [Edited He writes some fabulous stuff but there isn't any evidence that he's written anything using source filters that he considers worthy of running in production.]

Modules you aren't supposed to use anyway

• Lingua-Romana-Perligata
• Perl6-Currying
• Perl6-Export
• Perl6-Placeholders
• Perl6-Rules
• Switch

Attribute-Handlers-Prospective is the only module that was superceded by other things. You shouldn't use it.

He said Inline-Files is production worthy but its marked as experimental in its pod?

He uses Smart-Comments and Toolkit as development aides. It turns out that you aren't supposed to use Smart-Comments in production anyway - its a design feature that they're easy to remove. So production code doesn't even touch a source filter.

Regarding Ovid's code. Its much easier to have a source filter when you're running it against code you control and with some known code standards. Its much less sane to do that when you're releasing things onto CPAN where it will have to deal with anything that's potentially available.

I assert that Ovid's anecdotal evidence does not indicate that source filters are ok for general use on CPAN.