use 5.010;  # need perl 5.10+ regex enhancements -- (?|alts)

use warnings;
use strict;

use Regexp::Common qw(number);

my $str = '10,101,110.11010110,123,101.010E-01';
# offsets: 0123456789012345678901234567890123456789
#                    1         2         3

my $bin_int  = qr{ $RE{num}{int} {-keep}{-base=>2} }xms;
my $bin_real = qr{ $RE{num}{real}{-keep}{-base=>2} }xms;

my $binary = qr{ (?| $bin_int | $bin_real) }xms;

MATCH:
while ($str =~ m{ \b $binary \b }xmsg) {

    my $entire      = $1;
    my $fraction    = $6;
    my $exponential = $8;

    my $expon = defined $exponential && length $exponential;
    my $real  = ! $expon && defined $fraction && length $fraction;

    next MATCH unless length $entire;

    printf  "matched '%s' at offset %d; is %s \n",
        $entire, $-[1],
        $expon ? 'exponential' :
        $real  ? 'real'        :
                 'integer'  # default
        ;

    }