small improvement to roles mechanism

[Joachim Breitner]

Hi,

Am Freitag, den 11.10.2013, 22:19 -0400 schrieb Richard Eisenberg:
> 2. Like #1, but disallow Coercible. This way, the abstraction problem
> is no worse than it was before. (Apologies to Joachim if he minds this
> suggestion.)

I don’t mind it; after all I was reluctant to put Coercible in 7.8 in
the first place.

OTOH, Coercible is like GND: A feature that is more type-safe with Roles
than without, but it could live on its own. So if we do disable
role-checking in 7.8, we could still leave Coercible in as a tech
preview, with a clear statement in the docs saying “this is currently an
unsafe feature (like unsafeCoerce)”. I would be nice if adventurous
people can play with it.

Greetings,
Joachim


-- 
Joachim “nomeata” Breitner
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