This is probably not helpful but it is fun. :P

use strictures;
use List::Util "shuffle";

# Randomize the order
my @stuf = shuffle qw( namem1100.111 namem0900.111 namem0010.111 namep
+0000.111
                       namep0800.111 namep9999.111 );

print join("\n", "Before-", @stuf), $/;

# Update: didn't mean to leave this -> no warnings "uninitialized";
@stuf = map $_->[0],
    sort { $a->[3] <=> $b->[3] }
    map { /name([mp])(\d{4}\.\d{3})/;
          [ $_, $1, $2, $1 eq "m" ? (0-$2) : (0+$2) ] }
    @stuf;

print join("\n", "After-", @stuf), $/;
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See Schwartzian Transform and https://en.wikipedia.org/wiki/Schwartzian_transform.