… A connection between parametricity and representational abstraction was first suggested by
JC … We use relational parametricity to construct a model for an Algol-like language in which …

… to certain other forms of parametricity proposed in the literature. The form of parametricity we
… the correct number of elements in a constructive sense, ie it is isomorphic to the target type. …

… We call such environment entries type isomorphism assumptions. Syntactically, type “names…
be assigned any other type that is isomorphic to τ . Type isomorphism, in turn, is defined by …

… parametricity. In this paper we have seen that dinaturality coincides with naturality on
isomorphisms. In … to PER mod- els in which the parametricity given by dinaturality is vacuous: the …

… Extension Lemma holds only up to isomorphism, our framework can also uniformly subsume
strict models of parametricity, for which the Identity Extension Lemma holds on the nose. …

… -style translation is isomorphic to the inductivestyle translation. If an inductive constructor
has recursive arguments that are functions, our proof of the isomorphism needs the function …

… is intended to guarantee parametricity and representation … Our logical relation enables
us to establish parametricity and … between positive and negative notions of parametricity. …

… It is this parametricity property that we will use to prove the isomorphisms in Section 3. …
We first do the direction that does not require parametricity: …

… We show later that isomorphisms like this are intimately related to the Pi Theorem from
dimensional analysis described in Section 22, and for first-order types prove its programming …

… numeral, and hence does not satisfy binary parametricity. Rasmus Møgelberg [28] claims …
unary parametricity. This shows that unary parametricity does not imply binary parametricity. …