When I used lt instead of < operator, it works as you expected. Still, lt operator used for comparing strings not for numerals. As per my understanding, perl tries to implicitly convert both $i and 1 as strings and do comparison. If somebody finds different reason for it, kindly clarify me.

my $range = 0.1;
my $i = 0;
while( $i lt 1 )
{
    print $i."\n";    
    $i = $i + $range;
}
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