During my first steps in perlgolf I've encountered a strange m//g behaviour (perl 5.8.1).

When I run following code: 

#!/usr/bin/perl -l

$_="123"; @a=/./g;            print "#1: ",   /./g;
$_="123"; $a=/./g;            print "#2: ",   /./g;
$_="123";    /./g;            print "#3: ",   /./g;
$_="123";    /./g;            print "#4: ", /\G./g;
$_="123";    /./g; undef pos; print "#5: ",   /./g;
$_="123";    /./g; undef pos; print "#6: ", /\G./g;
$_="123";    /./g; pos = 2;   print "#7: ",   /./g;
$_="123";    /./g; pos = 2;   print "#8: ", /\G./g;

[download]

I get this output: 

#1: 123
#2: 23
#3: 23
#4: 23
#5: 123
#6: 123
#7: 3
#8: 3

[download]

This test shows that:

  1. In scalar context m//g doesn't return size of the list it would give back when called in list context,
  2. The \G anchor is useless - perlre states, that it should be used only at the beginning of pattern,
  3. and most important - m//g in scalar context doesn't reset pos (matches only once).

I ask you if it's proper behaviour / undocumented feature / bug? Or maybe I have missed something?

PS. My username is kokr but somehow email with my passwd can't find it's way to my mailbox :>

In reply to m//g behaves strange... by Anonymous Monk

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