New feature: initialization keyword arguments.

[sod] / doc / syntax.tex

diff --git a/doc/syntax.tex b/doc/syntax.tex
index b18acd5..3034b1e 100644 (file)
--- a/doc/syntax.tex
+++ b/doc/syntax.tex
@@ -585,6 +585,7 @@ class Sub : Super {
 
 <class-item> ::= <slot-item>
 \alt <initializer-item>
+\alt <initarg-item>
 \alt <fragment-item>
 \alt <message-item>
 \alt <method-item>
@@ -663,7 +664,7 @@ class Example : Super {
 \begin{grammar}
 <initializer-item> ::= @["class"@] <list>$[\mbox{@<slot-initializer>}]$ ";"
 
-<slot-initializer> ::= <dotted-name> "=" <initializer>
+<slot-initializer> ::= <dotted-name> @["=" <initializer>@]
 
 <initializer> :: <c-fragment>
 \end{grammar}
@@ -676,6 +677,22 @@ The first component of the @<dotted-name> must be the nickname of one of the
 class's superclasses (including itself); the second must be the name of a
 slot defined in that superclass.
 
+An @|initarg| property may be set on an instance slot initializer (or a
+direct slot definition).  See \xref{sec:concepts.lifecycle.birth} for the
+details.  An initializer item must have either an @|initarg| property, or an
+initializer expression, or both.
+
+Each class may define at most one initializer item with an explicit
+initializer expression for a given slot.
+
+\subsubsection{Initarg items}
+\begin{grammar}
+<initarg-item> ::=
+  "initarg"
+  @<declaration-specifier>^+
+  <list>$[\mbox{@<init-declarator>}]$ ";"
+\end{grammar}
+
 \subsubsection{Fragment items}
 \begin{grammar}
 <fragment-item> ::= <fragment-kind> "{" <c-fragment> "}"