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<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'>Get in the habit of putting the following
at the top of every file:<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'> use
strict;<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'>Try it. It will inform you that you
are implicitly doing just what you claim you are not doing: you have declared
(or, as you put it “redeclared”) the variable. “Use
strict” will protest because implicit declarations are often an accident;
which is clearly appropriate for your case.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'>By the way, I take exception to your
statement “. . . should make it global across all name spaces.”
No such concept exists in Perl. You declared the variable to be in the “main”
namespace; which you seemingly understood when you used “$::c”, the
naked double-colon being an alias for “main::”. The
package “main” is in force until you declare otherwise.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'>Alexander Danel<o:p></o:p></span></font></p>
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<p class=MsoNormal><b><font size=2 face=Tahoma><span style='font-size:10.0pt;
font-family:Tahoma;font-weight:bold'>From:</span></font></b><font size=2
face=Tahoma><span style='font-size:10.0pt;font-family:Tahoma'> chicago-talk-bounces+danel=speakeasy.net@pm.org
[mailto:chicago-talk-bounces+danel=speakeasy.net@pm.org] <b><span
style='font-weight:bold'>On Behalf Of </span></b>Mithun Bhattacharya<br>
<b><span style='font-weight:bold'>Sent:</span></b> Wednesday, March 03, 2010
8:20 PM<br>
<b><span style='font-weight:bold'>To:</span></b> chicago-talk@pm.org<br>
<b><span style='font-weight:bold'>Subject:</span></b> [Chicago-talk] Global
variable behavior</span></font><o:p></o:p></p>
</div>
<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'><o:p> </o:p></span></font></p>
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<p class=MsoNormal><font size=3 face=Arial><span style='font-size:12.0pt;
font-family:Arial'>Hi Everyone,<br>
<br>
A piece of my code is behaving in a way I didn't expect and I was hoping
someone could enlighten me as to why..<br>
</span></font><br>
-------------------------------------<br>
<font size=2><span style='font-size:10.0pt'>$ cat a.pl <br>
push @INC, '.';<br>
<br>
our $c = 15;<br>
<br>
require newbie;<br>
</span></font>-------------------------------------<br>
<font size=2><span style='font-size:10.0pt'>$ cat newbie.pm <br>
package newbie;<br>
<br>
print "first attempt: " . $c . "\n";<br>
print "second attempt: " . $::c . "\n";<br>
<br>
1;<br>
</span></font>-------------------------------------<br>
<font size=2><span style='font-size:10.0pt'>$ perl a.pl <br>
first attempt: <br>
second attempt: 15</span></font><br>
-------------------------------------<br>
<font face=Arial><span style='font-family:Arial'><br>
The way I see it the </span></font><font face="Courier New"><span
style='font-family:"Courier New"'>our</span></font><font face=Arial><span
style='font-family:Arial'> in </span></font><font face="Courier New"><span
style='font-family:"Courier New"'>a.pl</span></font><font face=Arial><span
style='font-family:Arial'> should make it global across all namespaces. The
second attempt does seem to say that did take place. What I am not sure is why
the </span></font><font face="Courier New"><span style='font-family:"Courier New"'>$c</span></font><font
face=Arial><span style='font-family:Arial'> variable has become local in scope
even though I haven't re-declared or redefined it in any way inside </span></font><font
face="Courier New"><span style='font-family:"Courier New"'>newbie.pm</span></font><font
face=Arial><span style='font-family:Arial'>.<br>
<br>
<br>
<br>
<br>
- Mithun</span></font><o:p></o:p></p>
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<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'><o:p> </o:p></span></font></p>
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