Sat 25 Jan 2020 09:30 - 10:00 at Orleans - Gradual Criteria Chair(s): Amal Ahmed

What is a good gradual language? Siek et al. have previously proposed the refined criteria, which specify certain guarantees about semantic correspondence and preservation of well-typedness and type-safety in the presence of untyped code. However, because of their exclusive focus on syntactic properties, they are not the whole story. Rich semantic properties like parametricity or non-interference, which hold in the static language, should also continue to hold upon gradualisation.

In this paper, we investigate and argue for a new criterion previously hinted at by Devriese et al.: the embedding from the static to the gradual language should be fully abstract. We illustrate in a simple setting that the criterion is useful; it can weed out an erroneous gradualisation that satisfies the refined criteria. We illustrate that it is realistic, by giving a proof sketch for the natural gradualisation of $\operatorname{STLC}_\mu$.

Sat 25 Jan Times are displayed in time zone: (GMT-06:00) Saskatchewan, Central America change

 09:00 - 10:00: WGT - Gradual Criteria at Orleans Chair(s): Amal AhmedNortheastern University, USA 09:00 - 09:30Talk Gradual Typing as if Types MatteredRonald GarciaUniversity of British Columbia, Éric TanterUniversity of Chile Pre-print 09:30 - 10:00Talk Fully Abstract from Static to GradualKoen JacobsKU Leuven, Amin Timanyimec-Distrinet KU-Leuven, Dominique DevrieseVrije Universiteit Brussel Pre-print