Merge pull request modelica#3386 from henrikt-ma/evaluable-attributes

Specify attributes of built-in types that are evaluable

chapters/classes.tex

@@ -1552,11 +1552,18 @@ \subsection{Real Type}\label{real-type}
 \index{unbounded@\robustinline{unbounded}!attribute of \robustinline{Real}}%
 \index{stateSelect@\robustinline{stateSelect}!attribute of \robustinline{Real}}
 
+The following attributes shall be evaluable: \lstinline!quantity!, \lstinline!unit!, \lstinline!displayUnit!, \lstinline!fixed!, and \lstinline!stateSelect!.
+
 The \lstinline!unit! and \lstinline!displayUnit! attributes may be either the empty string or a string matching \lstinline[language=grammar]!unit-expression! in \cref{unit-expressions}.
 The meaning of the empty string depends on the context.
 For the input and output components of a function, the empty string allows different units to be used in different calls to the function.
 For a non-function component, the empty string allows the unit (or display unit) to be inferred by the tool.
 
+\begin{nonnormative}
+That \lstinline!displayUnit! is evaluable allows tools to verify that the default display unit is consistent with the \lstinline!unit!.
+Unlike the \lstinline!unit!, \lstinline!displayUnit! is just a default, tools may allow using other compatible display units for a translated model.
+\end{nonnormative}
+
 The \lstinline!nominal! attribute is meant to be used for scaling purposes and to
 define tolerances in relative terms, see \cref{attributes-start-fixed-nominal-and-unbounded}.
 
@@ -1588,6 +1595,8 @@ \subsection{Integer Type}\label{integer-type}
 \index{start@\robustinline{start}!attribute of \robustinline{Integer}}%
 \index{fixed@\robustinline{fixed}!attribute of \robustinline{Integer}}
 
+The following attributes shall be evaluable: \lstinline!quantity!, and \lstinline!fixed!.
+
 The minimal recommended number range for \lstinline!IntegerType! is from -2147483648 to +2147483647, corresponding to a two's-complement 32-bit integer implementation.
 
 The fallback value is the closest value to $0$ consistent with the \lstinline!min! and \lstinline!max! bounds.
@@ -1608,6 +1617,8 @@ \subsection{Boolean Type}\label{boolean-type}
 \index{start@\robustinline{start}!attribute of \robustinline{Boolean}}%
 \index{fixed@\robustinline{fixed}!attribute of \robustinline{Boolean}}%
 
+The following attributes shall be evaluable: \lstinline!quantity!, and \lstinline!fixed!.
+
 The fallback value is \lstinline!false!.
 
 \subsection{String Type}\label{string-type}
@@ -1626,6 +1637,8 @@ \subsection{String Type}\label{string-type}
 \index{start@\robustinline{start}!attribute of \robustinline{String}}%
 \index{fixed@\robustinline{fixed}!attribute of \robustinline{String}}
 
+The following attributes shall be evaluable: \lstinline!quantity!, and \lstinline!fixed!.
+
 A \lstinline!StringType! value (such as $\langle\mathit{value}\rangle$ or other textual attributes of built-in types) may contain any Unicode data (and nothing else).
 
 The fallback value is \lstinline!""!.
@@ -1752,6 +1765,8 @@ \subsubsection{Attributes of Enumeration Types}\label{attributes-of-enumeration-
 end E;
 \end{lstlisting}
 
+The following attributes shall be evaluable: \lstinline!quantity!, and \lstinline!fixed!.
+
 The fallback value is the \lstinline!min! bound.
 
 \begin{nonnormative}