#!/usr/bin/perl
use strict;
use warnings;

while (<DATA>) {
  print /^(?=.*\d)[\d.-]+$/ ?
    "THIS LINE WORKS: $_" :
    "THIS LINE DOESN'T: $_";
}

__DATA__
.........---------........
...............1..........
...----1.................
-----------1-------------
.........................
-------------------------
...................-1d...
--------------------2---.
.-.-.-.-.3983943959359395
342094242.---------------
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