Beefy Boxes and Bandwidth Generously Provided by pair Networks
There's more than one way to do things

comment on

( #3333=superdoc: print w/replies, xml ) Need Help??

Hi. I'm a newbie Perl programmer (but a relatively experienced programmer in C) and I'm having trouble understanding the use of global variables in Perl. I would appreciate if people could help me.

The problem that I'm having is actually very simple: how exactly do I define (rather than declare) a global variable in Perl? (I know that declaring the variable may be done with use vars.)

I see that even under use strict, I don't have to declare/define global variables in Perl: I just need to fully qualify them and they're already there. Is this correct? If it is, then is there any kind of "super" use strict, which helps me catch typos that my programs may have?

Also, is there any way of defining a variable like C's static (i.e., a global variable with local scope). I see that Perl's our is almost what I want, but the variable declared with our in a function is still accessible outside the function if I use the variable's fully qualified name. I fear that I don't completely understand our.

In fact, I have trouble understanding the difference between our ($i); and use vars qw($i); Can anybody help with the difference? They don't seem different to the eyes of this poor Perl newbie.

Thanks in advance for any comments.

In reply to Help needed understanding global variables in Perl by Anonymous Monk

Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post; it's "PerlMonks-approved HTML":

  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.
  • Log In?

    What's my password?
    Create A New User
    and the web crawler heard nothing...

    How do I use this? | Other CB clients
    Other Users?
    Others contemplating the Monastery: (3)
    As of 2020-10-24 12:18 GMT
    Find Nodes?
      Voting Booth?
      My favourite web site is:

      Results (243 votes). Check out past polls.