Beefy Boxes and Bandwidth Generously Provided by pair Networks
Just another Perl shrine
 
PerlMonks  

Comment on

by gods
on Feb 11, 2000 at 00:06 UTC ( #3333=superdoc: print w/replies, xml ) Need Help??
While a variable is a string and if it has neither been assigned a value nor numified its value will be '', I am not sure on this but I think '' or undef or 0 can be interchanging depending on the context that the null variable scalar is used under (i.e when a scalar which's null is numified its value becomes 0).

Isn't this behaviour mainly hiding ugly bugs?
This behavior seems consistent and indeed in/of use, for instance, consider when quickly wanting to start a counter:

C:\Documents and Settings>perl - print "$hash{count} \n"; print -$hash{count},"\n"; print --$hash{count},"\n"; print ++$hash{count},"\n"; __END__ 0 -1 0 C:\Documents and Settings>

Update: did s/' '/''/, thanks Jenda for noticing the unintended typo as '' and ' ' are not the same thing. Added technical corrections too..



Excellence is an Endeavor of Persistence. A Year-Old Monk :D .

In reply to Re: Numification of strings by biohisham
in thread Numification of strings by LanX

Title:
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?
    Username:
    Password:

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

    How do I use this? | Other CB clients
    Other Users?
    Others chilling in the Monastery: (2)
    As of 2016-09-25 01:09 GMT
    Sections?
    Information?
    Find Nodes?
    Leftovers?
      Voting Booth?
      Extraterrestrials haven't visited the Earth yet because:







      Results (462 votes). Check out past polls.