I find it quite logical $1 contains the last capture. After all, you'd expect $v to be 3 in 
    $v = $_ for 1, 2, 3;

[download]
as well (I hope).

Here's a way to capute the first character: 

    $ perl -wle 'm[^(?{undef $var})(?:([01])(?{$var //= $^N}))+$] 
      and print "$_: '"'"'$var'"'"'" for qw[ 0 1 00 11 10 01 012]'
    0: '0'
    1: '1'
    00: '0'
    11: '1'
    10: '1'
    01: '0'

[download]

Abigail

In reply to Re: Regex failure interpretation by Abigail-II
in thread Regex failure interpretation by BrowserUk

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