I'm reading through Learning Perl and stuck looking at one example over and over. Can someone tell me how this regex works? 
$_ = "yabba dabba doo";
if (/y(.)(.)\2\1/) { # matches 'abba'
   print "It matched a after the y";
}

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It looks like the first (.)\2 would match ab, but the next (.)\1 would only match bb? I know I'm reading it incorrectly just begging for a plain explanation of whats going on there. Thanks!

In reply to Regex from Learning Perl by Anonymous Monk

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