Language extension histories

[ÉRDI Gergő]

On Sat, 31 Oct 2020, David Feuer wrote:

> I'm working on some code I want to be compatible with multiple GHC versions and I'm
> trying to figure out which language extensions I can reasonably use. I definitely need
> usable fancy pattern synonyms (not the bare-bones ones in 7.8). So that should set a
> lower bound, but I don't remember where. 7.10? 8.0?

Looking at Git, if you need record syntax support in pattern synonyms, you 
will need to go with 8.0.