So, if I'm interpreting your (rather terse) message correctly, because 2**63 is greater than a signed 64-bit int, it gets coersed into a double; before the subtraction is done.

And because 63-bits of precision is greater than the 53 bits the double can retain, by the time the subtraction is done, the loss of precision causes the problem.

In anycase, 1<<63-1 is a much nicer way of writing that constant. Thanks!

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In reply to Re^2: Range iterator outside integer range ... Why? by BrowserUk
in thread Range iterator outside integer range ... Why? by BrowserUk

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