RFC: Can DefaultSignature compile-time conditional APIs be regarded "benign"?

[Herbert Valerio Riedel]

Bas van Dijk <v.dijk.bas at gmail.com> writes:

[...]

> There's one minor issue: Say some client does not intend to rely on
> DefaultSignatures but forgets to write a definition for the method. He
> will then not get a "No explicit method or default declaration"
> warning. However, in this case I think the benefits outweigh this
> disadvantage.

...maybe the following shameless plug offers a different perspective
in the design-space of DefaultSignatures:

 http://hackage.haskell.org/trac/ghc/ticket/7395#comment:7

But I'm not sure yet, whether handling DefaultSignatures implementations
more like builtin classes and keeping vanilla H98 typeclass
default-implementations in separate "namespace" would actually help
here...