Ignorance? I'm just figuring this stuff out now, too :-)

1 - correct. Specifically, at the front of @INC.

2 - correct. Specifically, at the front of @INC (in front of the handler that ifdef put in)

2.1 - when the module is loaded, perl looks at @INC, finds perl5lib, finds the file there, loads it, and compiles it. During that compilation, it sees...

3 - incorrect. It sees the use ifdef, but doesn't reload ifdef (it's already loaded). It does, however, call ifdef->import(). This action turns around, figures out what ifdef parameter was passed on the original commandline (it's stored in an environment variable), and then calls the source filter on your code immediately. Once the source filter is done, perl continues parsing and compiling the rest of your module.

So, actually, it's not as convoluted as you may have thought. ;-) It does seem very convoluted, though.

In reply to Re^5: ifdef in modules by Tanktalus
in thread ifdef in modules by Anonymous Monk

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