I don’t object.   (They’d be orphan instances, so the interface file will always be loaded; but that’s probably ok.

From: Shayan Najd [mailto:sh.najd@gmail.com]
Sent: 02 August 2017 11:50
To: ghc-devs@haskell.org
Cc: Simon Peyton Jones <simonpj@microsoft.com>; Alan & Kim Zimmerman <alan.zimm@gmail.com>
Subject: Restructuring hsSyn

Currently AST declarations, their relate utilities, and `Outputable` instances are defined in the same files.

Does anyone object to moving `Outputable` instances to separate files? 

The purpose is to gradually identify reusable functionalities, group them together, polish them (e.g., remove some unnecessary dependencies), and expose them to the end-users.

At this stage, I don't expect any changes outside hsSyn.

/Shayan