X-Git-Url: https://git.distorted.org.uk/~mdw/sod/blobdiff_plain/74bf1b29b8cef573908180e6ab00cfeb6f324b46..1edb774eed8bea3f6dbde5b02db6ecd209394cf8:/doc/structures.tex diff --git a/doc/structures.tex b/doc/structures.tex index 37ca9e3..01e1ecd 100644 --- a/doc/structures.tex +++ b/doc/structures.tex @@ -30,8 +30,14 @@ classes and associated metadata. Note that Sod's object system is very flexible and it's possible for an extension to define a new root class which works very differently from the standard @|SodObject| described here. -The concrete types described in \xref{sec:structures.common} and -\ref{sec:structures.root} are declared by the header file @||. +The concrete types described in +\xref[\instead{sections}]{sec:structures.common} and +\ref{sec:structures.root} are declared by the header file +@||.\footnote{% + This isn't completely true. The @|SodObject| and @|SodClass| structures + are defined in a header called @||, which is generated by + the Sod translator; but @|| includes @||, so you + can forget about this detail.} % The definitions described in \xref{sec:structures.layout} are defined in the header file generated by the containing module. @@ -45,7 +51,7 @@ structure. Instance chains contain slots and vtable pointers, as described below. All instances have the basic structure of a @|struct sod_instance|. -\begin{describe}[struct sod_instance]{type} +\begin{describe}{ty}[struct sod_instance] {struct sod_instance \{ \\ \ind const struct sod_vtable *_vt; \-\\ \};} @@ -57,7 +63,7 @@ instances have the basic structure of a @|struct sod_instance|. \end{description} \end{describe} -\begin{describe}[struct sod_vtable]{type} +\begin{describe}{ty}[struct sod_vtable] {struct sod_vtable \{ \\ \ind const SodClass *_class; \\ size_t _base; \-\\ @@ -87,6 +93,12 @@ metaclass, and @|SodClass| is a subclass of @|SodObject|. Extensions can define additional root classes, but this is tricky, and not really to be recommended. +The class definitions shown in the synopses are intended to be informative, +but are fictional and can't really work: these classes are really defined by +Lisp code in the Sod translator, in order to deal with the circularities +involved at the top of the class/metaclass graph (see +\xref{sec:concepts.metaclasses.runtime}). + \subsection{The SodObject class} \label{sec:structures.root.sodobject} @@ -118,11 +130,11 @@ recommended. \label{fig:structures.root.sodobject} \end{figure} -\begin{describe}[SodObject]{cls} +\begin{describe}{cls}[SodObject] {[nick = obj, metaclass = SodClass, lisp_metaclass = sod_class] \\ class SodObject \{ \\ \ind - void init(?); + void init(?); \-\\ \}} The @|SodObject| class defines no slots. Because @|SodObject| has no @@ -139,7 +151,7 @@ recommended. The following messages are defined. - \begin{describe}[obj.init]{msg}{void init(?);} + \begin{describe}{msg}[obj.init]{void init(?);} Initialize a newly allocated instance. This message uses a custom method combination which works like the @@ -171,7 +183,7 @@ recommended. \xref{sec:concepts.lifecycle.birth}. \end{describe} - \begin{describe}[obj.teardown]{msg}{int teardown();} + \begin{describe}{msg}[obj.teardown]{int teardown();} Teardown an instance which is no longer required. The message returns an integer flag. A zero value means that the @@ -199,7 +211,7 @@ recommended. \subsection{The SodClass class} \label{sec:structures.root.sodclass} -\begin{describe}[SodClass]{cls} +\begin{describe}{cls}[SodClass] {[nick = cls, link = SodObject] \\ class SodClass: SodObject \{ \\ \ind const char *name; \\ @@ -289,7 +301,7 @@ recommended. \end{description} \end{describe} -\begin{describe}[struct sod_chain]{type} +\begin{describe}{ty}[struct sod_chain] {struct sod_chain \{ \\ \ind size_t n_classes; \\ const SodClass *const *classes; \\ @@ -410,7 +422,7 @@ and this is followed by corresponding members \end{prog} for each of $C$'s superclasses $A$ in the same chain in some (unimportant) order. The (somewhat obtuse) purpose of this union is to engage the `common -initial sequence' rule of \cite[6.5.2.3]{ISO:1990:IIP,ANSI:1999:AII}. +initial sequence' rule of \cite[6.5.2.3]{iso-1990:c,ansi-1999:c}. \subsubsection{The ichain structure} The @|ichain| structure contains (in order), a pointer