my $x does actually change the value of $x .

Update: That's wrong. I don't know why I wrote that. As far as I know my creates a new variable so the later references to $x actually refer to a different instance of a variable even though they have the same name.

For example this code: 
print __LINE__ . ": $x\n";
my $x = 123;
print __LINE__ . ": $x\n";
my $x = 456;
print __LINE__ . ": $x\n";
my $x;
print __LINE__ . ": $x\n";

[download]
Prints out: 
1: 
3: 123
5: 456
7:

[download]

In reply to Re^3: Trying to understand closures by superfrink
in thread Trying to understand closures by shine22vn

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