So I have a rules-lawyering question about how specified the overflow behavior is for the types Int and Word. * In the Haskell 2010 report it seems to be specified that (sections 18.1, 23.1): "All arithmetic is performed modulo 2^n, where n is the number of bits in the type." And this seems to apply to Int and Word as well as Int8, Word8, Int16, Word16, Int32, Word32, Int64, Word64. * However, in the Haskell 98 report ---and this verbiage is retained in the same section of H2010--- there is no such guarantee (section 6.4): "The results of exceptional conditions (such as overflow or underflow) on the fixed-precision numeric types are undefined; an implementation may choose error (_|_, semantically), a truncated value, or a special value such as infinity, indefinite, etc." * However, the FFI addendum to H98 does specify modulo behavior for the Int8, Word8, Int16, Word16, Int32, Word32, Int64, Word64 types (section 5.3): "There is, however, the additional constraint that all arithmetic on the fixed-sized types is performed modulo 2^n." But it is unclear whether this also applies to Int and Word. So when it comes to interpreting the report(s) and ensuring proper implementation, which is it? Are Int and Word arithmetic modular, or not? Did the specification change between H98 and H98+FFI or between H98+FFI and H2010? -- Live well, ~wren