One-shot semantics in GHC event manager

[Mikhail Glushenkov]

Hi,

On 17 October 2014 16:27, Austin Seipp <austin at well-typed.com> wrote:
> The catch with such a change is that there is no macro to determine
> whether we're using 7.8.3 or 7.8.4, so it's harder for users to figure
> things out (they have to use `MIN_VERSION_base` from Cabal). But maybe
> that doesn'tm atter too much. So, yes, I think it's doable, but that's
> a sticky bit.

Recent versions of Cabal (1.20+) define a MIN_TOOL_VERSION macro
similar to MIN_VERSION_.

So you can use '#if MIN_TOOL_VERSION_ghc(7,8,4)' to detect GHC 7.8.4.