are the "Pad" functions ones that (as mentioned above) are willing not just to add padding but to chop off higher-order digits? I find the name misleading.
Yes, and I agree the name is misleading. Does anyone have a suggestion of a better name?
Also hexPad and intAtBasePad each add (compared to the non-Pad versions) an Int argument, but octPad adds an Int and a Maybe Int argument? why is this? That's not right - don't know how that error happened, perhaps a toy-version of the library was loaded. Here is a copy paste of the type signature and some uses:
Prelude Text.PrettyPrint> :i octPad octPad :: (Integral a) => a -> Int -> Doc Prelude Text.PrettyPrint> octPad 10 2 12 Prelude Text.PrettyPrint> hexPad 133 3 085 Prelude Text.PrettyPrint> hexPad 133 2 85 Prelude Text.PrettyPrint> hexPad 133 1 5