use strict;
use warnings;


sub add{
    
    my ($x, $y) = @_;
    my $sum = $x + $y;
    print "Sum within function: $sum\n";    
    return ($sum);
}

my $bb=\&add(10,1); 
print $bb."\n"; 

my $cc=\&add; 

print $cc."\n";

[download]
Result 
Sum within function: 11
SCALAR(0x3f7e24)
CODE(0xa3e58c)

[download]
\&add(10,1) is not a code reference but a reference to the result of &add(10,1)

use strict;
use warnings;

our $static_counter = 1;

sub add{
    
    my ($x, $y) = @_;
    my $sum = $x + $y;
    print "Sum within function: $sum\n";    
    return ($sum);
}

sub counter {
    my $cnt = $static_counter++;
    print "Value of count in subroutine  $cnt\n";
    return($cnt);
}

sub mm{
    my ($x, $y, $add_ref, $counter_ref) = @_;
    
    my $cnt_in;
    my $add_in;
    my $mul = 1;
    

    
    $mul = ($x * $y * &$add_ref(10,1) * &$counter_ref());
    print "Multi : $mul\n";    
    
    $add_in = $add_ref->(20,5);  ### Getting Error Here 
    ###  Not a Code Reference
    $mul = ($x * $y * $add_in * $counter_ref->()); 
    print "Multi : $mul\n";         
    
    return $mul;
    
}

sub aa {    
    my $z; 
    $z =  mm(4,5, \&add, \&counter);
    $z =  mm(4,5, \&add, \&counter);
}


aa();

[download]
result 
Sum within function: 11
Value of count in subroutine  1
Multi : 220
Sum within function: 25
Value of count in subroutine  2
Multi : 1000
Sum within function: 11
Value of count in subroutine  3
Multi : 660
Sum within function: 25
Value of count in subroutine  4
Multi : 2000

[download]

In reply to Re: Not Coder reference error - when i pass function by Refernce by huck
in thread Not Coder reference error - when i pass function by Refernce by pks283

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