I am seeing both of them used in this script I am trying to debug and the literature is just not clear. Can someone demystify this for me?
Dynamic Scoping. It is a neat concept. Many people don't use it, or understand it.
Basically think of my
as creating and anchoring a variable to one block of {}, A.K.A. scope.
my $foo if (true); # $foo lives and dies within the if statement.
So a my
variable is what you are used to. whereas with dynamic scoping $var can be declared anywhere and used anywhere.
So with local
you basically suspend the use of that global variable, and use a "local value" to work with it. So local
creates a temporary scope for a temporary variable.
$var = 4;
print $var, "\n";
&hello;
print $var, "\n";
# subroutines
sub hello {
local $var = 10;
print $var, "\n";
&gogo; # calling subroutine gogo
print $var, "\n";
}
sub gogo {
$var ++;
}
This should print:
4
10
11
4