I'd run it through perltidy (on SourceForge, I believe) first, so the structure is workable. You might also use B::Deparse, to get it it something resembling actual code. Then read it. All of it. Print it out and mark it up, if necessary. 4000 lines translates to ~60 pages, at 8 point font. That's not too awful.

Having read it, you might have noticed duplications or near duplications. There's your chance to factor out common code into subroutines. This also allows you better encapsulation -- you can use lexicals instead of globals, passing in and receiving data. The program will get shorter and shorter, as you do this.

Based on my experiences reworking File::Find (soon, soon), you may be able to cut out 25% or more of the code.

(Extra free advice: wouldn't it be nice if this old code had unit tests, so you could change things and verify it still performed as expected? Someday, your code will be maintained. Make life easier for someone else.)

In reply to Re: Best way to fix a broken but functional program? by chromatic
in thread Best way to fix a broken but functional program? by idnopheq

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