It would be a premature pessimisation to move to using Math::BigInt on a 32-bit integer machine until you've exploited the ability of doubles to hold 53-bit integers accurately. That would make the breakpoint: 9007199254740992.

If there is any chance of a version of perl using something other than a 64-bit double, then you can determine the break point dynamically using: 

my $n = 2;
$n *=2 until $n+0.5 == $n; 
$n *=2; 
print $n;

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In reply to Re: portably finding max integer by BrowserUk
in thread portably finding max integer by martin

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