This works... I'm not sure what the "%"s in your regex were for. 
#!/usr/bin/perl

$text = "<!--begin-->this is a line of text<!--end--><!--begin-->anoth
+er one<!--end-->";

@lines = $text =~ /<\!--begin-->(.*?)<\!--end-->/g;
foreach (@lines) {
  print $_ . "\n";
}

[download]

Peace!
LassiLantar

In reply to Re: extract substring between token a and token b by LassiLantar
in thread extract substring between token a and token b by philosophia

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