First attempt at environments for operator/function definitions, with…

… application to 'previous'

chapters/synchronous.tex

@@ -554,14 +554,16 @@ \section{Clocked State Variables}\label{clocked-state-variables}
 
 The previous value of a clocked variable can be accessed with the \lstinline!previous! operator.  A variable to which \lstinline!previous! has been applied is called a \firstuse{clocked state variable}.
 
-\begin{longtable}[]{|l|p{12cm}|}
-\hline \endhead
-\lstinline!previous(u)! &
+\begin{operatordefinition}[previous]
+\begin{synopsis}\begin{lstlisting}[language=synopsis]
+previous(u)
+\end{lstlisting}\end{synopsis}
+\begin{semantics}
 The input argument is a \emph{component expression} (see \cref{argument-restrictions-component-expression}) or a parameter expression.  The return argument has the same type as the input argument.
 Input and return arguments are on the same clock.  At the first tick of the clock of \lstinline!u! or after a reset transition (see \cref{reset-handling}), the start value of \lstinline!u! is
 returned, see \cref{initialization-of-clocked-partitions}.  At subsequent activations of the clock of \lstinline!u!, the value of \lstinline!u! from the previous clock activation is returned.\\
-\hline
-\end{longtable}
+\end{semantics}
+\end{operatordefinition}
 
 \section{Partitioning Operators}\label{partitioning-operators}
 

preamble.tex

@@ -170,6 +170,33 @@
 \newenvironment{definition}{\begin{definition@inner}}{\qed\end{definition@inner}}
 \makeatother
 
+\newtheoremstyle{modelicadefinition}
+  {\topsep}   % ABOVESPACE
+  {\topsep}   % BELOWSPACE
+  {}          % BODYFONT
+  {}          % INDENT (empty value is the same as 0pt)
+  {\bfseries} % HEADFONT
+  {\\}        % HEADPUNCT
+  {.75em}     % HEADSPACE
+  {#1~#2. \texttt{#3}} % CUSTOM-HEAD-SPEC
+\theoremstyle{modelicadefinition}
+\newtheorem{operatordefinition}{Operator}[chapter]
+\crefname{operatordefinition}{operator}{operators}
+\Crefname{operatordefinition}{Operator}{Operators}
+\newtheorem{functiondefinition}{Function}[chapter]
+\crefname{functiondefinition}{function}{functions}
+\Crefname{functiondefinition}{Function}{Functions}
+
+\newenvironment{synopsis}{%
+~\vspace*{-\parskip}\par
+}{%
+}
+\newenvironment{semantics}{%
+\list{}{\setlength{\leftmargin}{1em}}\item[]%
+}{%
+\endlist
+}
+
 \setcounter{secnumdepth}{5}
 % Note: Toc changed for appendex
 \setcounter{tocdepth}{1}
@@ -217,6 +244,13 @@
     basicstyle=\upshape\ttfamily,              % Font size for inline code snippets.
 }
 
+\lstdefinelanguage{synopsis}[]{modelica}{% Language for use with the \lstinline command.
+    basicstyle=\upshape\ttfamily,              % Same size as \lstinline
+    frame=none,
+    aboveskip=0pt,
+    xleftmargin=1em
+}
+
 % Note: within only a keyword in grammar
 \lstdefinelanguage{grammar}{%
     basicstyle=\upshape\small\ttfamily,        % size of fonts used for the code