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<p class="MsoNormal">Dear GHC Steering Committee<o:p></o:p></p>
<p class="MsoNormal">I’m recommending acceptance of Proposal #378: <a href="https://github.com/ghc-proposals/ghc-proposals/pull/378">
Support the design for dependent types</a><o:p></o:p></p>
<p class="MsoNormal">As you’ll see, there is a lot of useful context, but the payload is pretty simple<o:p></o:p></p>
<p style="margin-left:36.0pt"><i>When evaluating new proposals, the GHC committee would consider compatibility with
<a href="https://gitlab.haskell.org/ghc/ghc/-/wikis/dependent-haskell">the proposed design sketch of dependent types on the GHC wiki</a>. Generally speaking, new proposals should be forward-compatible with the design sketch; that is, the new features proposed
would continue to be at home when surrounded by other dependent-type features.<o:p></o:p></i></p>
<p style="margin-left:36.0pt"><i>Of course, the committee remains free to revise the design sketch or to accept proposals that encroach upon it (i.e. contradicting this guidance), but such choices should be made explicitly.<o:p></o:p></i></p>
<p style="margin-left:36.0pt"><i>See also the committee's <a href="https://github.com/ghc-proposals/ghc-proposals/#review-criteria">
Review Criteria</a>: put another way, this proposal says that we consider the design sketch alongside other features of today's Haskell when assessing a new proposal's fit with the language.<o:p></o:p></i></p>
<p style="margin-left:36.0pt"><i>Note that compatibility with dependent types is far from the only criterion the committee would use to evaluate a proposal. Other review criteria, such as learnability, clarity of error messages, performance, etc., remain just
as ever.<o:p></o:p></i></p>
<p class="MsoNormal">Any views? Let’s try to converge rapidly…. the proposal has been substantially refined by a lot of debate.<o:p></o:p></p>
<p class="MsoNormal">Simon<o:p></o:p></p>
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