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Re: [perl #20827] Unexpected scientific notation.

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John Peacock
February 11, 2003 14:22
Re: [perl #20827] Unexpected scientific notation.
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Abigail wrote:
> If this "some point" isn't at the maximum size of what fits in an
> integer, than I think this fact should be documented clearly. If there's
> no indication where this "some point" is, it would reduce the value of
> -Dusemorebits to below the level of "useful".

Except that will be different for 64-bit vs 32-bit machines.  Not to mention 
strange machines (ISTR Cray's have odd opinions of what integers and floats 
should cover).

> Or is it even so
> 1001 ** 2 can't be garanteed to stringify to 1002001?

That's a completely different issue.  Where the NV default stringification 
switches to exponential notation is a complete different issue from where the 
default mathematics switches to NV instead of IV.

> I most certainly do think it's a bug. The number to be squared was
> carefully picked to be less than the square root of 0x7FFFFFFFFFFFFFFF.

But the fact that _you_ know the exponent will fit doesn't easily translate into 
Perl being able to forsee that.  I'll try and look at the core logic when I get 


John Peacock
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