Re^2: Scope, package, and 'my' variables

Thanks for the example. Minor quibble, perhaps it's my 5.8 system, but that second print statement does not fail as undefined. Instead it prints '1'.

#!/usr/bin/perl -w
use strict;

my $x = 1;
BEGIN { $x = 2; }
print $x, "\n"; # 1

BEGIN { my $x = 1; }
print $x, "\n"; # (sic: ) undefined, failure under strict.pm
    # Apr 30, 05:  Actually, mine doesn't fail and prints '1'

my $x = 1;    # 'my' generates a 'masks declaration' warning
{
    package foo;
    $x = 2;
}
print $x, "\n"; # 2

my $x = 1;    # 'my' generates a 'masks declaration' warning
{
    package foo;
    my $x = 2;
}
print $x, "\n"; # 1
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Re^3: Scope, package, and 'my' variables by revdiablo (Prior) on Apr 30, 2005 at 17:56 UTC
Each example must be run separately. You're getting the value of $x defined from the previous test. If you run the 2nd one by itself, however: `$ perl -le ' BEGIN { my $x = 1; } print defined $x ? "defined" : "undefined";' undefined` [download] And with strict: `$ perl -Mstrict -le ' BEGIN { my $x = 1; } print $x;' Global symbol "$x" requires explicit package name at -e line 2. Execution of -e aborted due to compilation errors.` [download]	[reply] [d/l] [select]

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Re^3: Scope, package, and 'my' variables
by revdiablo (Prior) on Apr 30, 2005 at 17:56 UTC

Each example must be run separately. You're getting the value of $x defined from the previous test. If you run the 2nd one by itself, however:

$ perl -le '
    BEGIN { my $x = 1; }
    print defined $x
          ? "defined"
          : "undefined";'
undefined
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And with strict:

$ perl -Mstrict -le '
    BEGIN { my $x = 1; }
    print $x;'
Global symbol "$x" requires explicit package name at -e line 2.
Execution of -e aborted due to compilation errors.
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