Typeclass for right monoid actions?

[madgen]

Can we perhaps have a typeclass for right monoid actions as well? Something called RightAction perhaps and maybe even have LeftAction which aliases Action?

[byorgey]

That sounds reasonable. I'd be happy to consider a pull request which adds this.

I'm curious to hear about your use case / application for RightAction.

[madgen]

It's a bit of work in progress, but I'm working on a monoid that unifiers associativity, precedence, fixity for pretty printers and parenthesising expressions turn out to be monoid actions. It's a left monoid action if the child is going to appear to the left of the parent operator and a right monoid action if it is to the right. Sorry, it's a bit sketchy at moment. I'd be happy to keep you posted when I make some more progress.

As for the PR, I'll send one this week. Thanks!