Of course it is true. The whole reason BEGIN blocks were created was so that useing a module could force the module's run time to happen before the remainder of the useing code's compile time so that the run-time states could impact how the remaining Perl code is parsed.

In the general case, reliably parsing Perl code that uses a module requires one to run the Perl code (and perhaps even XS code) of the used module. This is also true for BEGIN blocks not implied by use statements.

Ok, that's a reasonable explanation. Do you know whether there are any examples of this that aren't Source-Filter related issues ?

I believe that modules which change code semantics aren't really relevant to this issue, only those which change how code is parsed for the purposes of simple static analysis.

And the PPI documentation covers quite a bit of this. So if you use PPI for implementing your IDE, then your IDE will simply not be able to handle some Perl code. For many people, the Perl code that they deal with is rarely such that PPI actually fails on it (how fully and correctly PPI parses it is surely more variable, though I haven't seen good data on this). In fact, the author of PPI reports that almost everything on CPAN (excluding some things) can be parsed as well as PPI tries to.
Well that's good. With the size of CPAN, that's a pretty good indicator that a PPI-based approach would be very effective for use in an IDE.

But trying to pretend that the parsing problem doesn't in fact exist is just silly, IMHO.
You're right, of course.

I wonder if anything can be done (perhaps in the area of machine-readable POD) to make it easier for IDE implementors to deal with such issues.

-David

In reply to Re^3: Slow evolution of Perl = Perl is a closed Word (use) by erroneousBollock
in thread Slow evolution of Perl = Perl is a closed Word by Anonymous Monk

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