in reply to Re^3: scope of my $x in if statements
in thread scope of my $x in if statements

Just a nit, unless one is concerned that this $x should be out of scope after the end of the if block. The outer scope could have its own $x, for example.

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Re^5: scope of my $x in if statements
by ikegami (Patriarch) on May 08, 2009 at 03:32 UTC
    Limiting the scope to the if doesn't limit the lifetime of the value for destruction purposes (see if(my) scope), and if the outer scope already has an $x, you'll get a warning (easily fixed by using curlies or the other alternative I posted).
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      Agreed, except that the warning isn't always produced, depending on the surrounding scopes.

      use strict;
use warnings;

my $x = "outermost x";

print "alternative 1\n";
if( e() ) {

    my $x = f();

    if( $x and g($x) ) {
        print "inside the inner if \$x = $x\n";
    }
    print "after the inner if \$x = $x\n";
}

print "after the outer if \$x = $x\n";

print "\nalternative 2\n";
if( e() ) {

    if( my $x = f() ) {
        if( g($x) ) {
            print "inside the inner if \$x = $x\n";
        }
    }
    print "after the inner if \$x = $x\n";
}

print "after the outer if \$x = $x\n";



sub e {
    return "sub e here";
}

sub f {
    return "sub f here";
}

sub g {
    return "sub g here";
}


__END__

alternative 1
inside the inner if $x = sub f here
after the inner if $x = sub f here
after the outer if $x = outermost x

alternative 2
inside the inner if $x = sub f here
after the inner if $x = outermost x
after the outer if $x = outermost x

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