Hello! On 2014-10-24 at 10:08:00 +0200, Simon Peyton Jones wrote:

I replied, but failed to press "Submit" (which is several screenfuls away). Sorry

Thanks! (if you press the 'z'-key outside of any input-form on code-revision pages, you get the screen horizontally tiled with the submit-form in the bottom half - this is sometimes generally useful to have IMHO)

The Maybe DataCon idea looks right to me.

FWIW I *hate* the way that TidyPgm is forced to predict what CorePrep will do. I've created https://ghc.haskell.org/trac/ghc/ticket/9718 to explain.

Btw, this reminds me I have a low-priority plan to improve the `mkInteger` call interface, as the current one is terrible: it requires splitting a large integer literal into 31-bit words (even when machine wordsize is 64bit!), and then wrapping those into an ordinary [Int]-list. I'd rather like mkInteger to take an packed array of machine-size words, similar to how [Char] literals are handled via `unpackCString#`, which would allow for a more compact representation in object files as well as possibly direct conversion of integer literals in GHC's Integer backends... I've created a ticket to keep track of that idea: https://ghc.haskell.org/trac/ghc/ticket/9719 Cheers, hvr