Update invariants section

examples/scholarly_paper/2021-ITP-PMTI/ROOT

@@ -18,6 +18,8 @@ session "2021-ITP-PMTI" = "Isabelle_DOF" +
     "figures/invariant-checking-violated-example.png"
     "figures/inherited-invariant-checking-violated-example.png"
     "figures/term-context-checking-example.png"
+    "figures/term-context-failed-checking-example.png"
     "figures/term-context-evaluation-example.png"
+    "figures/term-context-failed-evaluation-example.png"
     "figures/term-context-equality-evaluation-example.png"
     "lstisadof.sty"

examples/scholarly_paper/2021-ITP-PMTI/document/lstisadof-manual.sty

@@ -0,0 +1,298 @@
+%% Copyright (C) 2018 The University of Sheffield
+%%               2018-2021 The University of Paris-Saclay
+%%               2019-2021 The University of Exeter
+%%
+%% License:
+%%   This program can be redistributed and/or modified under the terms
+%%   of the LaTeX Project Public License Distributed from CTAN
+%%   archives in directory macros/latex/base/lppl.txt; either
+%%   version 1.3c of the License, or (at your option) any later version.
+%%   OR
+%%   The 2-clause BSD-style license.
+%%
+%%   SPDX-License-Identifier: LPPL-1.3c+ OR BSD-2-Clause
+\usepackage{listings}
+\usepackage{listingsutf8}
+\usepackage{tikz}
+\usepackage[many]{tcolorbox}
+\tcbuselibrary{listings}
+\tcbuselibrary{skins}
+\usepackage{xstring}
+
+\definecolor{OliveGreen}    {cmyk}{0.64,0,0.95,0.40}
+\definecolor{BrickRed}      {cmyk}{0,0.89,0.94,0.28}
+\definecolor{Blue}          {cmyk}{1,1,0,0}
+\definecolor{CornflowerBlue}{cmyk}{0.65,0.13,0,0}
+
+
+
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%% <antiquotations>
+%% Hack: re-defining tag types for supporting highlighting of antiquotations
+\gdef\lst@tagtypes{s}
+\gdef\lst@TagKey#1#2{%
+    \lst@Delim\lst@tagstyle #2\relax
+        {Tag}\lst@tagtypes #1%
+                     {\lst@BeginTag\lst@EndTag}%
+        \@@end\@empty{}}
+\lst@Key{tag}\relax{\lst@TagKey\@empty{#1}}
+\lst@Key{tagstyle}{}{\def\lst@tagstyle{#1}}
+\lst@AddToHook{EmptyStyle}{\let\lst@tagstyle\@empty}
+\gdef\lst@BeginTag{%
+    \lst@DelimOpen
+        \lst@ifextags\else
+        {\let\lst@ifkeywords\iftrue
+         \lst@ifmarkfirstintag \lst@firstintagtrue \fi}}
+\lst@AddToHookExe{ExcludeDelims}{\let\lst@ifextags\iffalse}
+\gdef\lst@EndTag{\lst@DelimClose\lst@ifextags\else}
+\lst@Key{usekeywordsintag}t[t]{\lstKV@SetIf{#1}\lst@ifusekeysintag}
+\lst@Key{markfirstintag}f[t]{\lstKV@SetIf{#1}\lst@ifmarkfirstintag}
+\gdef\lst@firstintagtrue{\global\let\lst@iffirstintag\iftrue}
+\global\let\lst@iffirstintag\iffalse
+ \lst@AddToHook{PostOutput}{\lst@tagresetfirst}
+ \lst@AddToHook{Output}
+     {\gdef\lst@tagresetfirst{\global\let\lst@iffirstintag\iffalse}}
+ \lst@AddToHook{OutputOther}{\gdef\lst@tagresetfirst{}}
+\lst@AddToHook{Output}
+    {\ifnum\lst@mode=\lst@tagmode
+         \lst@iffirstintag \let\lst@thestyle\lst@gkeywords@sty \fi
+         \lst@ifusekeysintag\else \let\lst@thestyle\lst@gkeywords@sty\fi
+     \fi}
+\lst@NewMode\lst@tagmode
+\gdef\lst@Tag@s#1#2\@empty#3#4#5{%
+    \lst@CArg #1\relax\lst@DefDelimB {}{}%
+        {\ifnum\lst@mode=\lst@tagmode \expandafter\@gobblethree \fi}%
+        #3\lst@tagmode{#5}%
+    \lst@CArg #2\relax\lst@DefDelimE {}{}{}#4\lst@tagmode}%
+\gdef\lst@BeginCDATA#1\@empty{%
+    \lst@TrackNewLines \lst@PrintToken
+    \lst@EnterMode\lst@GPmode{}\let\lst@ifmode\iffalse
+    \lst@mode\lst@tagmode #1\lst@mode\lst@GPmode\relax\lst@modetrue}
+%
+\def\beginlstdelim#1#2#3%
+{%
+    \def\endlstdelim{\texttt{\textbf{\color{black!60}#2}}\egroup}%
+    \ttfamily\textbf{\color{black!60}#1}\bgroup\rmfamily\color{#3}\aftergroup\endlstdelim%
+}
+%% </antiquotations>
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%% <isar>
+\providecolor{isar}{named}{blue}
+\renewcommand{\isacommand}[1]{\textcolor{OliveGreen!60}{\ttfamily\bfseries #1}}
+\newcommand{\inlineisarbox}[1]{#1}
+\NewTColorBox[]{isarbox}{}{
+     ,boxrule=0pt
+     ,boxsep=0pt
+     ,colback=white!90!isar
+     ,enhanced jigsaw
+     ,borderline west={2pt}{0pt}{isar!60!black}
+     ,sharp corners
+     ,before skip balanced=0.5\baselineskip plus 2pt
+     % ,before skip=10pt
+     % ,after skip=10pt
+     ,enlarge top by=0mm
+     ,enhanced
+     ,overlay={\node[draw,fill=isar!60!black,xshift=0pt,anchor=north
+       east,font=\bfseries\footnotesize\color{white}]
+                at (frame.north east) {Isar};}
+}
+%% </isar>
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% 
+%% <out>
+\providecolor{out}{named}{green}
+\newtcblisting{out}[1][]{%
+      listing only%
+     ,boxrule=0pt
+     ,boxsep=0pt
+     ,colback=white!90!out
+     ,enhanced jigsaw
+     ,borderline west={2pt}{0pt}{out!60!black}
+     ,sharp corners
+     % ,before skip=10pt
+     % ,after skip=10pt
+     ,enlarge top by=0mm
+     ,enhanced
+     ,overlay={\node[draw,fill=out!60!black,xshift=0pt,anchor=north
+       east,font=\bfseries\footnotesize\color{white}]
+                at (frame.north east) {Document};}
+        ,listing options={
+           breakatwhitespace=true
+          ,columns=flexible%
+          ,basicstyle=\small\rmfamily
+          ,mathescape
+          ,#1
+      }
+  }%
+%% </out>
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% 
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% 
+%% <sml>
+\lstloadlanguages{ML}
+\providecolor{sml}{named}{red}
+\lstdefinestyle{sml}{
+   basicstyle=\ttfamily,%
+   commentstyle=\itshape,%
+   keywordstyle=\bfseries\color{CornflowerBlue},%
+   ndkeywordstyle=\color{green},%
+   language=ML
+%  ,literate={%
+%     {<@>}{@}1%
+%    }
+   ,keywordstyle=[6]{\itshape}%
+   ,morekeywords=[6]{args_type}%
+   ,tag=**[s]{@\{}{\}}%
+   ,tagstyle=\color{CornflowerBlue}%
+   ,markfirstintag=true%
+}%
+\def\inlinesml{\lstinline[style=sml,breaklines=true,mathescape,breakatwhitespace=true]}
+\newtcblisting{sml}[1][]{%
+      listing only%
+     ,boxrule=0pt
+     ,boxsep=0pt
+     ,colback=white!90!sml
+     ,enhanced jigsaw
+     ,borderline west={2pt}{0pt}{sml!60!black}
+     ,sharp corners
+     % ,before skip=10pt
+     % ,after skip=10pt
+     ,enlarge top by=0mm
+     ,enhanced
+     ,overlay={\node[draw,fill=sml!60!black,xshift=0pt,anchor=north
+       east,font=\bfseries\footnotesize\color{white}]
+                at (frame.north east) {SML};}
+        ,listing options={
+          style=sml
+          ,columns=flexible%
+          ,basicstyle=\small\ttfamily
+          ,mathescape
+          ,#1
+      }
+  }%
+%% </sml>
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% 
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% 
+%% <latex>
+\lstloadlanguages{TeX}
+\providecolor{ltx}{named}{yellow}
+\lstdefinestyle{lltx}{language=[AlLaTeX]TeX,
+  ,basicstyle=\ttfamily%
+  ,showspaces=false%
+  ,escapechar=ë
+  ,showlines=false%
+  ,morekeywords={newisadof}
+ %  ,keywordstyle=\bfseries%
+   % Defining 2-keywords
+   ,keywordstyle=[1]{\color{BrickRed!60}\bfseries}%
+   % Defining 3-keywords
+   ,keywordstyle=[2]{\color{OliveGreen!60}\bfseries}%
+   % Defining 4-keywords
+   ,keywordstyle=[3]{\color{black!60}\bfseries}%
+   % Defining 5-keywords
+   ,keywordstyle=[4]{\color{Blue!70}\bfseries}%
+   % Defining 6-keywords
+   ,keywordstyle=[5]{\itshape}%
+  % 
+}
+\lstdefinestyle{ltx}{style=lltx,
+                basicstyle=\ttfamily\small}%
+\def\inlineltx{\lstinline[style=ltx, breaklines=true,columns=fullflexible]}
+% see
+% https://tex.stackexchange.com/questions/247643/problem-with-tcblisting-first-listed-latex-command-is-missing
+\NewTCBListing{ltx}{ !O{} }{%
+     listing only%
+     ,boxrule=0pt
+     ,boxsep=0pt
+     ,colback=white!90!ltx
+     ,enhanced jigsaw
+     ,borderline west={2pt}{0pt}{ltx!60!black}
+     ,sharp corners
+     % ,before skip=10pt
+     % ,after skip=10pt
+     ,enlarge top by=0mm
+     ,enhanced
+     ,overlay={\node[draw,fill=ltx!60!black,xshift=0pt,anchor=north
+       east,font=\bfseries\footnotesize\color{white}]
+                at (frame.north east) {\LaTeX};}
+      ,listing options={
+             style=lltx,
+            ,columns=flexible%
+            ,basicstyle=\small\ttfamily
+            ,#1
+       }
+  }%
+%% </latex>
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% 
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% 
+%% <bash>
+\providecolor{bash}{named}{black}
+\lstloadlanguages{bash}
+\lstdefinestyle{bash}{%
+   language=bash
+  ,escapechar=ë
+  ,basicstyle=\ttfamily%
+  ,showspaces=false%
+  ,showlines=false%
+  ,columns=flexible%
+ %  ,keywordstyle=\bfseries%
+   % Defining 2-keywords
+   ,keywordstyle=[1]{\color{BrickRed!60}\bfseries}%
+   % Defining 3-keywords
+   ,keywordstyle=[2]{\color{OliveGreen!60}\bfseries}%
+   % Defining 4-keywords
+   ,keywordstyle=[3]{\color{black!60}\bfseries}%
+   % Defining 5-keywords
+   ,keywordstyle=[4]{\color{Blue!80}\bfseries}%
+   ,alsoletter={*,-,:,~,/}
+   ,morekeywords=[4]{}%
+   % Defining 6-keywords
+   ,keywordstyle=[5]{\itshape}%
+  % 
+}
+\def\inlinebash{\lstinline[style=bash, breaklines=true,columns=fullflexible]}
+\newcommand\@isabsolutepath[3]{%
+  \StrLeft{#1}{1}[\firstchar]%
+  \IfStrEq{\firstchar}{/}{#2}{#3}%
+}
+
+\newcommand{\@homeprefix}[1]{%
+  \ifthenelse{\equal{#1}{}}{\textasciitilde}{\textasciitilde/}%
+}
+
+\newcommand{\prompt}[1]{%
+  \color{Blue!80}\textbf{\texttt{%
+    achim@logicalhacking:{\@isabsolutepath{#1}{#1}{\@homeprefix{#1}#1}}\$}}%
+}
+\newtcblisting{bash}[1][]{%
+      listing only%
+     ,boxrule=0pt
+     ,boxsep=0pt
+     ,colback=white!90!bash
+     ,enhanced jigsaw
+     ,borderline west={2pt}{0pt}{bash!60!black}
+     ,sharp corners
+     % ,before skip=10pt
+     % ,after skip=10pt
+     ,enlarge top by=0mm
+     ,enhanced
+     ,overlay={\node[draw,fill=bash!60!black,xshift=0pt,anchor=north
+       east,font=\bfseries\footnotesize\color{white}]
+                at (frame.north east) {Bash};}
+     ,listing options={
+           style=bash
+           ,columns=flexible%
+           ,breaklines=true%
+           ,prebreak=\mbox{\space\textbackslash}%
+           ,basicstyle=\small\ttfamily%
+           ,#1
+      }
+  }%
+%% </bash>
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% 

examples/scholarly_paper/2021-ITP-PMTI/paper.thy

@@ -431,13 +431,14 @@ text\<open>
   and can now be specified in common HOL syntax.
   One can now specify the constraints using the keyword \<^theory_text>\<open>invariant\<close> in the class definition.
   If we take back the ontology example for mathematical papers
-  of~@{cite "brucker.ea:isabelledof:2019"} (ADD LISTING REFERENCE!!!),
+  of~@{cite "brucker.ea:isabelledof:2019"} (see ADD LISTING REFERENCE!!!),
   it was proposed to specify some constraints like that any instance of a \<^emph>\<open>result\<close> class
   finally has a non-empty property list, if its \<^theory_text>\<open>kind\<close> is \<^theory_text>\<open>"proof"\<close>
   (see the \<^theory_text>\<open>invariant has_property\<close>), or that 
   the \<^theory_text>\<open>establish\<close> relation between \<^theory_text>\<open>claim\<close> and \<^theory_text>\<open>result\<close> must be defined when an instance
-  of the class \<^theory_text>\<open>conclusion\<close> is defined (see the \<^theory_text>\<open>invariant establish_defined\<close>). 
+  of the class \<^theory_text>\<open>conclusion\<close> is defined (see the \<^theory_text>\<open>invariant establish_defined\<close>).
-@{boxed_theory_text [display,indent=10, margin=70] \<open>
+\begin{figure}
+@{boxed_theory_text [display] \<open>
 doc_class author =
   email :: "string" <= "''''"
 doc_class text_section =
@@ -464,7 +465,9 @@ doc_class conclusion = text_section +
   invariant establisg_defined :: "\<forall> x. x \<in> Domain (establish \<sigma>)
                                            \<longrightarrow> (\<exists> y \<in> Range (establish \<sigma>). (x, y) \<in> establish \<sigma>)"
 \<close>}
-
+\caption{Excerpt of an ontology example for mathematical papers.}
+\label{fig-ontology-example}
+\end{figure}
 
   In our example, the invariant \<^theory_text>\<open>author_finite \<close> of the class \<^theory_text>\<open>introduction\<close> enforces
   that the user sets the \<^theory_text>\<open>authored_by\<close> set.
@@ -477,15 +480,21 @@ doc_class conclusion = text_section +
   of the future instance of the class \<^theory_text>\<open>conclusion\<close>.
   Now we can define some instances:
 
+\begin{figure}
 @{boxed_theory_text [display] \<open>
 text*[church::author, email="\<open>church@lambda.org\<close>"]\<open>\<close>
 
 text*[resultProof::result, evidence = "proof", property="[@{thm \<open>HOL.refl\<close>}]"]\<open>\<close>
 
+text*[resultProof2::result, evidence = "proof", property="[@{thm \<open>HOL.sym\<close>}]"]\<open>\<close>
+
 text*[introduction1::introduction, authored_by = "{@{author \<open>church\<close>}}", level = "Some 0"]\<open>\<close>
 
 text*[claimNotion::claim, authored_by = "{@{author \<open>church\<close>}}", based_on= "[\<open>Notion1\<close>, \<open>Notion2\<close>]", level = "Some 0"]\<open>\<close>
 \<close>}
+\caption{Some instances of the classes of the ontology in the \autoref{fig-ontology-example}.}
+\label{fig-instances-example}
+\end{figure}
 \<close>
 
 (*<*)
@@ -507,7 +516,7 @@ text\<open>
   constraint specified in the \<^theory_text>\<open>force_level\<close> invariant,
   when we specify the \<^theory_text>\<open>level\<close> attribute of \<^theory_text>\<open>introduction\<close> to \<^theory_text>\<open>Some 0\<close>.
   The \<^theory_text>\<open>force_level\<close> invariant forces the value of the argument
-  of the attribute \<^theory_text>\<open>level\<close> option type to be greater than 1.
+  of the attribute \<^theory_text>\<open>level\<close> to be greater than 1.
 \<close>
 
 figure*[
@@ -522,7 +531,7 @@ declare_reference*["inherited-invariant-checking-figure"::figure]
 (*>*)
 
 text\<open>
-  Classes inherit the invariants from their superclasses.
+  Classes inherit the invariants from their superclass.
   As the class  \<^theory_text>\<open>claim\<close> is a subsclass
   of the class \<^theory_text>\<open>introduction\<close>, it inherits the \<^theory_text>\<open>introduction\<close> invariants.
   Hence the \<^theory_text>\<open>force_level\<close> invariant is checked
@@ -538,35 +547,6 @@ figure*[
   from the class \<^theory_text>\<open>introduction\<close> and is violated by the instance \<^theory_text>\<open>claimNotion\<close>.
 \<close>
 
-(*
-text\<open>For example, with the following two classes:
-\<^theory_text>\<open>
-doc_class class_inv1 =
-  int1 :: "int"
-  invariant inv1 :: "int1 \<sigma> \<ge> 3"
-
-doc_class class_inv2 = class_inv1 +
-  int2 :: "int"
-  invariant inv2 :: "int2 \<sigma> < 2"
-\<close>
-
-  as the class  \<^theory_text>\<open>class_inv2\<close> is a subsclass
-  of the class \<^theory_text>\<open>class_inv1\<close>, it inherits \<^theory_text>\<open>class_inv1\<close> invariants.
-  Hence the \<^theory_text>\<open>inv1\<close> invariant is checked
-  when the instance \<^theory_text>\<open>testinv2\<close> is defined, like we can see in .
-
-  Now let's define two instances, one of each class:\<close>
-
-
-
-text\<open>
-\<^theory_text>\<open>
-text*[testinv1::class_inv1, int1=4]\<open>lorem ipsum...\<close>
-text*[testinv2::class_inv2, int1=3, int2=1]\<open>lorem ipsum...\<close>
-\<close>
-\<close>
-*)
-
 text\<open>
   The value of each attribute defined for the instances is checked against their classes invariants.
   As the class \<^theory_text>\<open>class_inv2\<close> is a subsclass of the class \<^theory_text>\<open>class_inv1\<close>,
@@ -574,37 +554,97 @@ text\<open>
   Hence the \<^theory_text>\<open>int1\<close> invariant is checked when the instance \<^theory_text>\<open>testinv2\<close> is defined.\<close>
 
 text\<open>
-  Isabelle/HOl provides commands which type-check and print terms (the command \<^theory_text>\<open>term\<close>)
+  To offer a smooth integration into the theory development process,
-  and evaluates and print a term (the command \<^theory_text>\<open>value\<close>).
+  Isabelle/HOL should be able to dynamically interpret the source document.
-  We provide the equivalent commands, respectively \<^theory_text>\<open>term*\<close> and \<^theory_text>\<open>value*\<close>.
+  But the specific antiquotations introduced by Isabelle/DOF are not directly recognized
-  These commands add up type-checking and expanding of isabelle/DOF antiquotations
+  by Isabelle/HOL, and the process of term checking and evaluation must be enriched.
-  in a own validation phase.
+  Previous works added a validation step fo the SML and semi-formal text contexts.
+  But to support Isabelle/DOF antiquotations in the term contexts, the validation step must
+  be enriched and a new step, which we call \<^emph>\<open>elaboration\<close> must be added to allow
+  these antiquotations in \<open>\<lambda>\<close>-terms.
+  The resulting process encompasses the following steps:
+    \<^item> Parse the term which represents the object;
+    \<^item> Infer the type of the term;
+    \<^item> Certify the term;
+    \<^item> Pass on the information to PIDE;
+    \<^item> Validate the term: the Isabelle/DOF antiquotations terms are parsed and type-checked;
+    Validate the term: a step to understand the reference
+      which refers to the object.
+
+      This step is mandatory because the ontology framework adds
+      up objects not directly recognized by Isabelle/HOL;
+
+    \<^item> Elaborate: the Isabelle/DOF antiquotations terms are expanded.
+      The antiquotations are replaced by the objects in HOL they reference
+      i.e. a \(\lambda\)-calculus term;
+    \<^item> Code generation:
+      \<^item> Evaluation of HOL expressions with ontological annotations,
+      \<^item> Implementation of the ontological invariants processed simultaneously
+        with the generation of the document (a theory in HOL).
+
+  Isabelle/HOL provides commands to type-check and print terms (the command \<^theory_text>\<open>term\<close>)
+  and evaluate and print a term (the command \<^theory_text>\<open>value\<close>).
+  We provide the equivalent commands, respectively \<^theory_text>\<open>term*\<close> and \<^theory_text>\<open>value*\<close>, which support
+  the validation and elaboration phase.
+  This allow a smooth integration into the \<^emph>\<open>formal\<close> theory development process.
+\<close>
+
+(*<*)
+declare_reference*["type-checking-example"::side_by_side_figure]
+(*>*)
+
+text\<open>
   For example one can now reference a class instance in a \<^theory_text>\<open>term*\<close> command:
 @{theory_text [display,indent=10, margin=70] \<open>  
 term*\<open>@{author \<open>church\<close>}\<close>
 \<close>}
 
 The term \<^theory_text>\<open>@{author \<open>church\<close>}\<close> is type-checked, \<^ie>, the command \<^theory_text>\<open>term*\<close> checks that
-\<^theory_text>\<open>church\<close> references a term of type \<^theory_text>\<open>author\<close>.
+\<^theory_text>\<open>church\<close> references a term of type \<^theory_text>\<open>author\<close>
-
+(see \<^side_by_side_figure>\<open>type-checking-example\<close>).
-  and the and we would like
-Isabelle to check that this instance is indeed an instance of this class.
-Here, we want to reference the instance \<^theory_text>\<open>@{docitem \<open>xcv4\<close>}\<close> previously defined.
-We can use the term* command which extends the classic term command
-and does the appropriate checking.
-@{theory_text [display,indent=10, margin=70] \<open>
-term*\<open>@{F \<open>xcv4\<close>}\<close>
-\<close>}
-We can also reference an attribute of the instance.
-Here we reference the attribute r of the class F which has the type @{typ \<open>thm list\<close>}.
-
-@{theory_text [display,indent=10, margin=70] \<open>
-term*\<open>r @{F \<open>xcv4\<close>}\<close>
-
-term \<open>@{A \<open>xcv2\<close>}\<close>
-\<close>}
 \<close>
 
+side_by_side_figure*[
+  "type-checking-example"::side_by_side_figure
+  , anchor="''fig-term-type-checking-ex''"
+  , caption="''church is an existing instance.''"
+  , relative_width="48"
+  , src="''figures/term-context-checking-example''"
+  , anchor2="''fig-term-type-checking-failed-ex''"
+  , caption2="''The churche instance is not defined.''"
+  , relative_width2="48"
+  , src2="''figures/term-context-failed-checking-example''"
+]\<open>Type-checking of antiquotations in term context.\<close>
+
+(*<*)
+declare_reference*["evaluation-example"::side_by_side_figure]
+(*>*)
+
+text\<open>
+ This \<^theory_text>\<open>value*\<close> command:
+@{theory_text [display,indent=10, margin=70] \<open>
+value*\<open>email @{author \<open>church\<close>}\<close>
+\<close>}
+
+type-checks the antiquotation \<^theory_text>\<open>@{author \<open>church\<close>}\<close>,
+and then returns the value of the \<^theory_text>\<open>email\<close> attribute for the \<^theory_text>\<open>church\<close> instance,
+\<^ie> the HOL string \<^term>\<open>''church@lambda.org''\<close>
+(see \<^side_by_side_figure>\<open>evaluation-example\<close>).
+\<close>
+
+side_by_side_figure*[
+  "evaluation-example"::side_by_side_figure
+  , anchor="''fig-term-evaluation-ex''"
+  , caption="''A Text-Element as Requirement.''"
+  , relative_width="48"
+  , src="''figures/term-context-evaluation-example''"
+  , anchor2="''fig-term-failed-evaluation-ex''"
+  , caption2="''Referencing a Requirement.''"
+  , relative_width2="48"
+  , src2="''figures/term-context-failed-evaluation-example''"
+]\<open>Evaluation of antiquotations in term context.\<close>
+
+(*
 figure*[
   "term-context-checking-example-figure"::figure
   , relative_width="99"
@@ -620,27 +660,27 @@ figure*[
 ]\<open>The invariant \<^theory_text>\<open>force_level\<close> of the class claim is inherited
   from the class \<^theory_text>\<open>introduction\<close> and is violated by the instance \<^theory_text>\<open>claimNotion\<close>.
 \<close>
+*)
 
-figure*[
+(*<*)
-  "term-context-equality-evaluation-figure"::figure
+declare_reference*["term-context-equality-evaluation"::figure]
-  , relative_width="99"
+(*>*)
-  , src="''figures/term-context-equality-evaluation-example''"
+
-]\<open>The invariant \<^theory_text>\<open>force_level\<close> of the class claim is inherited
+text\<open>
-  from the class \<^theory_text>\<open>introduction\<close> and is violated by the instance \<^theory_text>\<open>claimNotion\<close>.
+We can even compare classes. \<^figure>\<open>term-context-equality-evaluation\<close>
+shows that the two classes \<^theory_text>\<open>resultProof\<close> and \<^theory_text>\<open>resultProof2\<close> are not equivalent
+because their attribute \<^theory_text>\<open>property\<close> differ.
 \<close>
 
+figure*[
+  "term-context-equality-evaluation"::figure
+  , relative_width="80"
+  , src="''figures/term-context-equality-evaluation-example''"
+]\<open>Evaluation of the equivalence of two class instances.
+\<close>
 
-text\<open>We declare a new text element. Note that the class name contains an underscore "\_".\<close>
-text*[te::text_element]\<open>Lorem ipsum...\<close>
-
-text\<open>Unfortunately due to different lexical conventions for constant symbols and mixfix symbols
-     this term antiquotation has to be denoted like this: @{term\<open>@{text-element \<open>ee\<close>}\<close>}.
-     We need to substitute an hyphen "-" for the underscore "\_".\<close>
-term*\<open>@{text-element \<open>te\<close>}\<close>
 subsection\<open>Example and Queries\<close>
 
-section*["morphisms"::technical,main_author="Some(@{docitem ''idir''}::author)"] \<open>Proving Morphisms on Ontologies\<close>
-
 text\<open>
 A new mechanism to make query on instances is available and uses the HOL implementation of lists.
 So complex queries can be defined using functions over the instances list.
@@ -668,6 +708,8 @@ value*\<open>filter (\<lambda>\<sigma>. Z.z \<sigma> > 2) @{Z-instances}\<close>
 EXPLAIN VALUE* ???
 \<close>
 
+section*["morphisms"::technical,main_author="Some(@{docitem ''idir''}::author)"] \<open>Proving Morphisms on Ontologies\<close>
+
 section*[ontoexample::text_section,main_author="Some(@{docitem ''idir''}::author)"] \<open>Applications\<close>
 
 subsection\<open>Engineering Example : An Extract from PLib\<close>