--- a/Quotient-Paper/Paper.thy Wed Jun 16 03:47:38 2010 +0100
+++ b/Quotient-Paper/Paper.thy Wed Jun 16 14:26:23 2010 +0200
@@ -257,7 +257,7 @@
The paper is organised as follows: Section \ref{sec:prelims} presents briefly
some necessary preliminaries; Section \ref{sec:type} describes the definitions
of quotient types and shows how definitions of constants can be made over
- quotient types. Section \ref{sec:resp} introduces the notions of respectfullness
+ quotient types. Section \ref{sec:resp} introduces the notions of respectfulness
and preservation; Section \ref{sec:lift} describes the lifting of theorems;
Section \ref{sec:examples} presents some examples
and Section \ref{sec:conc} concludes and compares our results to existing
@@ -658,7 +658,7 @@
But this constant does \emph{not} respect @{text "\<alpha>"}-equivalence and
consequently no theorem involving this constant can be lifted to @{text
"\<alpha>"}-equated lambda terms. Homeier formulates the restrictions in terms of
- the properties of \emph{respectfullness} and \emph{preservation}. We have
+ the properties of \emph{respectfulness} and \emph{preservation}. We have
to slightly extend Homeier's definitions in order to deal with quotient
compositions.
@@ -692,18 +692,21 @@
@{text [display, indent=10] "REL (\<sigma>, \<tau>) c\<^isub>r c\<^isub>r"}
%%% PROBLEM I do not yet completely understand the
- %%% form of respectfullness theorems
+ %%% form of respectfulness theorems
%%%\noindent
%%%if @ {text \<sigma>} and @ {text \<tau>} have no type variables. In case they have, then
%%%the proof obligation is of the form
%%%
%%%@ {text [display, indent=10] "Quotient R\<^bsub>\<alpha>s\<^esub> Abs\<^bsub>\<alpha>s\<^esub> Rep\<^bsub>\<alpha>s\<^esub> implies REL (\<sigma>, \<tau>) c\<^isub>r c\<^isub>r"}
+ %%% ANSWER: The respectfulness theorems never have any quotient assumptions,
+ %%% So the commited version is ok.
+
\noindent
%%%where @ {text "\<alpha>s"} are the type variables in @{text \<sigma>} and @{text \<tau>}.
- Homeier calls these proof obligations \emph{respectfullness
+ Homeier calls these proof obligations \emph{respectfulness
theorems}. Before lifting a theorem, we require the user to discharge
- them. And the point with @{text bn} is that the respectfullness theorem
+ them. And the point with @{text bn} is that the respectfulness theorem
looks as follows
@{text [display, indent=10] "(\<approx>\<^isub>\<alpha> \<doublearr> =) bn bn"}
@@ -755,6 +758,14 @@
\noindent
under the assumption @{text "Quotient R Abs Rep"}.
+ %%% ANSWER
+ %%% There are 3 things needed to lift things that involve composition of quotients
+ %%% - The compositional quotient theorem
+ %%% - Compositional respectfullness theorems
+ %%% - and compositional preservation theorems.
+ %%% And the case of preservation for nil is special, because we prove some property
+ %%% of all elements in an empty list, so any property is true so we can write it
+ %%% more general, but a version restricted to the particular quotient is true as well
%%% PROBLEM I do not understand this
%%%This is not enough to lift theorems that talk about quotient compositions.
@@ -951,7 +962,7 @@
two terms, and is defined for a goal being a relation between these two terms.
\begin{itemize}
- \item For two constants, an appropriate constant respectfullness assumption is used.
+ \item For two constants, an appropriate constant respectfulness assumption is used.
\item For two variables, we use the assumptions proved in regularization.
\item For two abstractions, they are eta-expanded and beta-reduced.
\item For two applications, if the right side is an application of
@@ -1113,12 +1124,12 @@
"concat"} and theorems about it. We defined the composition of
relations and showed examples of compositions of quotients which
allows lifting polymorphic types with subtypes quotiented as well.
- We extended the notions of respectfullness and preservation;
+ We extended the notions of respectfulness and preservation;
with quotient compositions there is more than one condition needed
for a constant.
Our package is modularized, so that single definitions, single
- theorems or single respectfullness conditions etc can be added,
+ theorems or single respectfulness conditions etc can be added,
which allows the use of the quotient package together with
type-classes and locales. This has the advantage over packages
requiring big lists as input for the user of being able to develop
@@ -1135,8 +1146,8 @@
\medskip
\noindent
{\bf Acknowledgements:} We would like to thank Peter Homeier for the
- discussions about his HOL4 quotient package and explaining to us
- some its finer points in the implementation.
+ discussions about his HOL4 quotient package and explaining to us
+ some of its finer points in the implementation.
*}