Should the PVP be changed with regards to instances?

Henning Thielemann lemming at
Wed Dec 21 12:26:39 CET 2011

On Wed, 21 Dec 2011, John Lato wrote:

> On Wed, Dec 21, 2011 at 11:16 AM, Henning Thielemann
> <lemming at> wrote:
>> On Wed, 21 Dec 2011, John Lato wrote:
>>> I'm in the same situation, however I'm quite hesitant to add new
>>> instances in a minor version.  Adding new dependencies can cause
>>> breakage even without orphan instances, if downstream packages import
>>> a different version of that dependency already.
>> The proposal was about adding type class instances, not about adding package
>> dependencies.
> IME, new type class instances usually arise only because of new
> package dependencies or a major version bump to an existing
> dependency, either of which would currently require a major bump.

Adding a package dependency does not require a minor version bump. 
Increasing the imported version of a package dependency only requires a 
version bump if that changes the API. Thus I do not see a closer 
connection between adding instances and modifying package dependencies.

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