On 10 April 2006 22:41, Andy Gill wrote:

Why can't we just steal a bit in the (GHC) info table, rather than mess with LSB of pointers, or have two info tables?

Because you need one bit per constructor *instance*. eg. there are two variants of Just: the normal one, and the deepSeq'd one. So I either put the bit in the constructor instance itself, or I need one info table for each variant, or I need to distinguish based on the address of the closure. Cheers, Simon