I've found certain triplets of numbers that added up and put in a variable are, equal to 1, print as 1, are true on looks_like_number, match 1 when evaluated with eq but do not match 1 using using ==.

The order the numbers are added matters, the script below produces output in the form.

0.688 + 0.289 + 0.023
total is 1
looks like a number
fails on ==
matches on eq

0.688 + 0.023 + 0.289
total is 1
looks like a number
matches on ==
matches on eq

0.559 + 0.380 + 0.061
total is 1
looks like a number
matches on ==
matches on eq

#!/usr/bin/perl
use strict;
use warnings;
use Scalar::Util qw(looks_like_number);


while (<DATA>) {
    if (m{^#}) {
	print;
	next;
    }
    chomp;
    my ($x, $y, $z) = split(m{ });
#   my $var = $x + $y + $z;
    my $var = $x;
    $var += $y;
    $var += $z;
    
    print "$x + $y + $z\n";
    print "total is $var\n";
    if (looks_like_number($var)) { 
	print "looks like a number\n";
    }
    else {
	print "doesn't look like a number\n"
    }
    if ($var == 1) {
	print "matches on ==\n";
    }
    else {
	print "fails on ==\n";
    }
    if ($var eq 1) {
	print "matches on eq\n";
    }
    else {
	print "fails on eq\n"
    }
    print "\n";
}

__DATA__
#FAIL
0.688 0.289 0.023
0.500 0.422 0.078
0.693 0.290 0.017
0.207 0.563 0.230
0.491 0.421 0.088
0.498 0.420 0.082
0.696 0.285 0.019
0.693 0.286 0.021
0.517 0.409 0.074
# ORDER CHANGED 
0.688 0.023 0.289
0.422 0.078 0.500
# PASS
0.559 0.380 0.061
0.648 0.314 0.038
0.546 0.414 0.040
0.600 0.348 0.052
0.653 0.311 0.036
0.741 0.245 0.014
0.787 0.201 0.012
0.651 0.318 0.031
0.627 0.331 0.042

In reply to $var == 1 fails when $var = 1 by mjlush

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