Whenever I see the term source filter I am left wondering as to what it refers to. Aside from a formal definition, I think an example would also be helpful to drive the message home.

Has anybody found a good solution for lazily-evaluated lists in Perl? I've tried a number of ways to turn something like for my $item ( map { ... } @list ) { } into a lazy evaluation--by tie-i...

I understand that Smart::Comments should not be used in production code, since it is a source filter. However, I have been using Smart::Comments in my development code and then commenting out the...

It is "common knowledge" that source filters are bad and should not be used in production code. When answering a a similar, but more specific question I couldn't find any good references that expl...