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The YNot Project

The YNot Project

The goal of the Ynot project is to make programming with dependent types practical for a modern programming language. In particular, we are extending the Coq proof assistant to make it possible to write higher-order, imperative and concurrent programs (in the style of Haskell) through a shallow embedding of Hoare Type Theory (HTT). HTT provides a clean separation between pure and effectful computations, makes it possible to formally specify and reason about effects, and is fully compositional.

This was actually commented on here, by Greg Morrisett himself. Conceptually, this seems like it's related to Adam Chlipala's A Certified Type-Preserving Compiler from Lambda Calculus to Assembly Language. See, in particular, slides 23-24 of this presentation (PDF). More generally, computation and reflection seem to be gaining recognition as important features for the practical use of such powerful tools as Coq; see also SSREFLECT tactics for Coq and their accompanying paper A Small Scale Reflection Extension for the Coq system (PDF).

It's also interesting to observe that the work appears to depend on the "Program" keyword in the forthcoming Coq 8.2, the work behind which is known as "Russell," as referred to in this thread. Russell's main page in the meantime is here. Again, the point is to simplify programming with dependent types in Coq.

Update: Some preliminary code is available from the project page.