Hi,

I hit some strange behavior when doing simple comparisons of numbers with leading zeros.

I found that if I don't quote a number I am using for comparison, I sometimes get incorrect result.

Here is my code that demonstrates the issue: 

#!/usr/bin/perl -w
use strict;

my @numbers = qw(022000 022300 022400 022800 023600 024700 024500 0249
+00);

foreach my $number(@numbers)
{
    my $compRes1 = $number < 060000;
    my $compRes2 = $number < '060000';
    
    print "For $number, result1 is $compRes1, result2 is $compRes2\n";
    
    
}

[download]

Here is the output that I get:
For 022000, result1 is 1, result2 is 1
For 022300, result1 is 1, result2 is 1
For 022400, result1 is 1, result2 is 1
For 022800, result1 is 1, result2 is 1
For 023600, result1 is 1, result2 is 1
For 024700, result1 is , result2 is 1
For 024500, result1 is 1, result2 is 1
For 024900, result1 is , result2 is 1

As can be seen, for '024700' and '024900', result1 is empty while result2 is correct.

I tried this both on 32 and 64 bit Perl, older and newer versions.

I am not sure if this is a problem, just very strange.

Any ideas as to how this can happen are greatly appreciated.


Tim.

In reply to strange comparison results by sduser81

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