Re: Scoping Study Aid program

Scoping does make my brain hurt: I get:
Name "Our_package::my_variable" used only once: possible typo at scope.pl line 41.
for

print "4) \$Our_package::my_variable NOT DEFINED\n"
  if not (defined $Our_package::my_variable);
[download]

Shouldn't $Our_package::my_variable be something? I'm looking for a typo but ...

Comment on Re: Scoping Study Aid program Download Code

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Re: Re: Scoping Study Aid program by zeno (Friar) on Jan 16, 2001 at 14:14 UTC
I get: Name "Our_package::my_variable" used only once: possible typo at scope.pl line 41. for `print "4) \$Our_package::my_variable NOT DEFINED\n" if not (defined $Our_package::my_variable);` [download] Shouldn't $Our_package::my_variable be something? I'm looking for a typo but ... You're right! I get the warning, too, but I let this happen on purpose. This generates a warning because I purposely refer to a variable declared 'my my_variable' in the other package. Since it's declared with 'my', it is (let's see if I get this right) lexically scoped only to the other package, so the calling program can't see it. As I understand it, a variable with lexical scoping means that it only exists within a particular textual area of code, in this case, the package "Our_package". I guess a solution to this would be for me to change the `"#!/usr/bin/perl -w"` to `"#!/usr/bin/perl"`. Or maybe print a disclaimer about the warning. The point is, the user should learn from this that a '`my`' variable in a package is not visible from outside that package.	[reply] [d/l] [select]
Re: Re: Scoping Study Aid program by zeno (Friar) on Jan 16, 2001 at 14:18 UTC
I went ahead and changed the code and included a disclaimer. Enjoy! :) -tim	[reply]