Re^2: Error in my Regular expression pattern

[Anonymous Monk]

Like perlop#m/PATTERN/msixpodualgc ( perlop#m// ), says,

m// in scalar context returns true if it succeeds, false if it fails.

Each time m// succeeds against a variable, like when  $n = m/twinkle/ig; executes, position is changed, so that  while(/twinkle/ig) { executes, only the second twinkle is counted.

If you add this to your program before the while loop

 print "pos is ", pos, ", remainder '", substr($_, pos), "'\n";
pos($_) = undef;

this resets pos associated with $_, and then your program will produce

Number of occurences = 1
pos is 7, remainder ' twinkle little star'
Found 2 times

Like perlfaq4 says, if you want the number of occurances, use the flying lentil operator, use  my $count =()= m/twinkle/ig;