On Fri, Jul 27, 2012 at 03:06:04PM -0400, Edward Kmett wrote:
There is currently no way to know whether or not calling Data.Bits.bitSizewill crash your program.
I propose extending the Bits class to include:
hasBitSize :: Bits b => b -> Bool
such that it returns False for Integer and True for the other instances
Can you give an example of a situation in which you would use hasBitSize, and do something useful if it returned False? Would it be better to move bitSize into a separate class?
since the vast majority of instances are finite, it may be reasonable to set the default definition to
hasBitSize _ = False
Did you mean True? Either way, I think I would personally prefer not to have a default, so that people need to actually check existing instances. Thanks Ian