This module provides an opaque unsigned 64 bit value with the usual set of typeclass instances one would expect for a fixed width unsigned integer type. Operations like addition, subtraction and multiplication etc provide a "modulo 2^64" result as one would expect from a fixed width unsigned word.

This just re-exports the Word64 type defined in Data.Word plus some functions like plusCarrySum and timesCarryProd that do the normal addition and multiplication but provide a carry in addition to the regular operation.