Integers 64 - r3n/rebol-wiki GitHub Wiki

Minimum value: -9'223'372'036'854'775'808
equal to: - (2 ** 63)
Maximum value: 9'223'372'036'854'775'807
equal to: (2 ** 63) - 1

It's problematic to produce those values with the help of decimals, because of decimal precision. This works:

min-int: to integer! negate 2 ** 63

While this produces a number overflow:

max-int: to integer! 2 ** 63 - 1

The reason is, that the power operator (**) returns a decimal, which doesn't have all the precision needed.

Other ways that work:

min-int: to integer! #8000000000000000
min-int: to integer! #{8000 0000 0000 0000}
min-int: (negate to integer! 2 ** 62) - (to integer! 2 ** 62)
max-int: to integer! #7FFFFFFFFFFFFFFF
max-int: to integer! #{7FFF FFFF FFFF FFFF}
max-int: (to integer! 2 ** 62) - 1 + (to integer! 2 ** 62)