From 5f16ccbf3c91b290cb8eb4c1df1bccab5e5b3036 Mon Sep 17 00:00:00 2001 From: Ralf Jung <jung@mpi-sws.org> Date: Tue, 7 Feb 2017 13:12:54 +0100 Subject: [PATCH] docs: compsability --- docs/program-logic.tex | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/docs/program-logic.tex b/docs/program-logic.tex index f69a1a096..084200b03 100644 --- a/docs/program-logic.tex +++ b/docs/program-logic.tex @@ -12,7 +12,7 @@ The base logic described in \Sref{sec:base-logic} works over an arbitrary CMRA $ It turns out that we can generalize this further and permit picking CMRAs ``$\iFunc(\Prop)$'' that depend on the structure of assertions themselves. Of course, $\Prop$ is just the syntactic type of assertions; for this to make sense we have to look at the semantics. -Furthermore, there is a composeability problem with the given logic: if we have one proof performed with CMRA $\monoid_1$, and another proof carried out with a \emph{different} CMRA $\monoid_2$, then the two proofs are actually carried out in two \emph{entirely separate logics} and hence cannot be combined. +Furthermore, there is a composability problem with the given logic: if we have one proof performed with CMRA $\monoid_1$, and another proof carried out with a \emph{different} CMRA $\monoid_2$, then the two proofs are actually carried out in two \emph{entirely separate logics} and hence cannot be combined. Finally, in many cases just having a single ``instance'' of a CMRA available for reasoning is not enough. For example, when reasoning about a dynamically allocated data structure, every time a new instance of that data structure is created, we will want a fresh resource governing the state of this particular instance. @@ -53,7 +53,7 @@ Effectively, we just defined a way to instantiate the base logic with $\Res$ as We thus obtain all the rules of \Sref{sec:base-logic}, and furthermore, we can use the maps $\wIso$ and $\wIso^{-1}$ \emph{in the logic} to convert between logical assertions $\Sem\Prop$ and the domain $\iPreProp$ which is used in the construction of $\Res$ -- so from elements of $\iPreProp$, we can construct elements of $\Sem{\textlog M}$, which are the elements that can be owned in our logic. -\paragraph{Proof composeability.} +\paragraph{Proof composability.} To make our proofs composeable, we \emph{generalize} our proofs over the family of functors. This is possible because we made $\Res$ a \emph{product} of all the CMRAs picked by the user, and because we can actually work with that product ``pointwise''. So instead of picking a \emph{concrete} family, proofs will assume to be given an \emph{arbitrary} family of functors, plus a proof that this family \emph{contains the functors they need}. -- GitLab