Thank you for this example, the following one makes it even more obvious! 
use strict;
use warnings;


sub pr {

  my $ref= ref($_[0]) ? $_[0] : \$_[0];
  print $ref,"\t";      # print ref of para
}


check(qw/ Scalar 1 /);
check(qw/ Array [1,2] /);
check(qw/ Hash  {1,2} /);


sub check {
    my ($_title_,$type) = @_;
    my $_call_ ="pr $type;";
    my $code= <<"__EOC";
    for (1..3) {
    $_call_
        print "\\n\\t"; #UPDATE
    for (1..3) {
        $_call_
    }
    print "\\n";
}
__EOC
    print "\n--- $_title_ \n";
    print $code;
    eval $code;
}

[download]
OUTPUT 
--- Scalar 
    for (1..3) {
    pr 1;
        print "\n\t"; #UPDATE
    for (1..3) {
        pr 1;
        }
    print "\n";
}
SCALAR(0x818ad04)
        SCALAR(0x818acec)       SCALAR(0x818acf8)       SCALAR(0x818ac
+ec)
SCALAR(0x818acf8)
        SCALAR(0x818ad10)       SCALAR(0x818acec)       SCALAR(0x818ad
+10)
SCALAR(0x818acec)
        SCALAR(0x818ad04)       SCALAR(0x818ad10)       SCALAR(0x818ad
+04)

--- Array 
    for (1..3) {
    pr [1,2];
        print "\n\t"; #UPDATE
    for (1..3) {
        pr [1,2];
        }
    print "\n";
}
ARRAY(0x818acf8)
        ARRAY(0x818acd4)        ARRAY(0x818acd4)        ARRAY(0x818acd
+4)
ARRAY(0x818acd4) <----- FAILS
        ARRAY(0x818acf8)        ARRAY(0x818acf8)        ARRAY(0x818acf
+8)
ARRAY(0x818acf8)
        ARRAY(0x818acd4)        ARRAY(0x818acd4)        ARRAY(0x818acd
+4)

[download]
Thanks for teh discussion!!!

Cheers Rolf

In reply to Re^6: Reference of constants and literals by LanX
in thread Reference of constants and literals by LanX

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