Re: The -w switch on a web application

I could be on the wrong track here, however are you defining variables before you use them? The line:

  print "The string is $foo\n";
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may give you an "uninitialised value, as $foo may not be defined yet. whereas:

  my $foo;
  # some code
  print "The string is $foo\n";
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should be better - as $foo has been defined.. Referencing into hashes, only to discover that the particular key you're trying to use does not exists is another area that results in a very similar problem :)

-- Ian Stuart
A man depriving some poor village, somewhere, of a first-class idiot.

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Re: Re: The -w switch on a web application by davorg (Chancellor) on Jan 31, 2003 at 12:13 UTC
I think you're slightly confused about what these error messages mean. If you don't declare a variable, you'll get the "requires explicit package name" error. This is triggered by `use strict`, not by `-w`. `$ perl -Mstrict -le 'print $x' Global symbol "$x" requires explicit package name at -e line 1. Execution of -e aborted due to compilation errors.` [download] The error we're dicsussing here is seen whenever you try to print a variable that contains "undef" (even if it's previously been declared). This is triggered by `-w` (or `use warnings`). `$ perl -Mstrict -w -le 'print my $x' Use of uninitialized value in print at -e line 1.` [download] -- <http://www.dave.org.uk> "The first rule of Perl club is you do not talk about Perl club." -- Chip Salzenberg	[reply] [d/l] [select]

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Re: Re: The -w switch on a web application
by davorg (Chancellor) on Jan 31, 2003 at 12:13 UTC

I think you're slightly confused about what these error messages mean. If you don't declare a variable, you'll get the "requires explicit package name" error. This is triggered by use strict, not by -w.

$ perl -Mstrict -le 'print $x'
Global symbol "$x" requires explicit package name at -e line 1.
Execution of -e aborted due to compilation errors.
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The error we're dicsussing here is seen whenever you try to print a variable that contains "undef" (even if it's previously been declared). This is triggered by -w (or use warnings).

$ perl -Mstrict -w -le 'print my $x'
Use of uninitialized value in print at -e line 1.
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http://www.dave.org.uk

"The first rule of Perl club is you do not talk about Perl club."
-- Chip Salzenberg

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