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Re: Re: seeking different ways to slice a 2-d array

by samtregar (Abbot)
on Apr 25, 2002 at 08:06 UTC ( #161884=note: print w/replies, xml ) Need Help??


in reply to Re: seeking different ways to slice a 2-d array
in thread seeking different ways to slice a 2-d array

I'd like to read that again when it's updated to describe 'our'. I use 'our' all the time but the cross-over between the previously totally unrelated realms of lexical and package variables is still a bit vague in my mind.

-sam

  • Comment on Re: Re: seeking different ways to slice a 2-d array

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(jeffa) 3Re: seeking different ways to slice a 2-d array
by jeffa (Bishop) on Apr 25, 2002 at 14:42 UTC
    I am very curious to know why you use our so much. I have never had a reason to use it myself because i tend to use OO a lot.

    I recently had a big revelation at (jeffa) 3Re: Whether to use local(), hopefully this post will remove the vagueness from your mind as well.

    UPDATE:
    Oh $#!^ - you are Sam Tregar. Scratch that last sentance! :O

    jeffa

    L-LL-L--L-LL-L--L-LL-L--
    -R--R-RR-R--R-RR-R--R-RR
    B--B--B--B--B--B--B--B--
    H---H---H---H---H---H---
    (the triplet paradiddle with high-hat)
    
      I use it any time I would have used "use vars" in the past - to access package globals. The nice thing is that I can scope where that access is legal. So, if I've got a package global %CACHE and two routines read_cache and write_cache I can:
      sub read_cache { our %CACHE; ... } sub write_cache { our %CACHE; ... }
      And they'll access the same variable. But if I start refering to %CACHE inside some other routine I get an error just like if %CACHE had been a lexical. I like that.

      So, I guess I'm pretty happy with our. The only reason I want more education is that I learned about lexical and package variables as totally separate!!! and now they ain't... Which is cool, but also pretty bizarre.

      -sam

        I don't like to declare the same variable more than once.
        sub read_cache { our %CACHE; ... } sub write_cache { our %CACHF; ... }
        Oops. It's so easy to slip... But on the other hand, you have to misspell the variable throughout all of &write_cache, which usually isn't too probable. But for short routines--like get/set routines--it's a not too far-fetched scenario.

        For those times I prefer to use
        { our %CACHE; sub read_cache { ... } sub write_cache { ... } }
        The only reason I want more education is that I learned about lexical and package variables as totally separate!!! and now they ain't... Which is cool, but also pretty bizarre.

        I agree, it does indeed look like globals has become... something else. But you can relax--they haven't. They're still totally separate. What our() does is to declare a lexical alias for the global variable.

        Cheers,
        -Anomo

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