(alx-0014r6-C) Refactor syntax of macros

Signed-off-by: Alejandro Colomar <[email protected]>

Author: alejandro-colomar

source/preprocessor.tex

@@ -50,11 +50,8 @@
     include-directive\br
     pp-import\br
     embed-directive\br
-    \terminal{\# define } identifier replacement-list new-line\br
-    \terminal{\# define } identifier lparen \opt{identifier-list} \terminal{)} replacement-list new-line\br
-    \terminal{\# define } identifier lparen \terminal{... )} replacement-list new-line\br
-    \terminal{\# define } identifier lparen identifier-list \terminal{, ... )} replacement-list new-line\br
-    \terminal{\# undef \ } identifier new-line\br
+    define-directive\br
+    undef-directive\br
     \terminal{\# line \ \ } pp-tokens new-line\br
     \terminal{\# error \ } \opt{pp-tokens} new-line\br
     \terminal{\# warning} \opt{pp-tokens} new-line\br
@@ -106,22 +103,6 @@
     pp-tokens new-line
 \end{bnf}
 
-\begin{bnf}
-\nontermdef{lparen}\br
-    \descr{a \terminal{(} character not immediately preceded by whitespace}
-\end{bnf}
-
-\begin{bnf}
-\nontermdef{identifier-list}\br
-    identifier\br
-    identifier-list \terminal{,} identifier
-\end{bnf}
-
-\begin{bnf}
-\nontermdef{replacement-list}\br
-    \opt{pp-tokens}
-\end{bnf}
-
 \begin{bnf}
 \nontermdef{pp-tokens}\br
     preprocessing-token \opt{pp-tokens}
@@ -1455,6 +1436,35 @@
 \indextext{replacement!macro|see{macro, replacement}}%
 \indextext{preprocessing directive!macro replacement|see{macro, replacement}}
 
+\begin{bnf}
+\nontermdef{define-directive}\br
+    \terminal{\# define } identifier replacement-list new-line\br
+    \terminal{\# define } identifier lparen \opt{identifier-list} \terminal{)} replacement-list new-line\br
+    \terminal{\# define } identifier lparen \terminal{... )} replacement-list new-line\br
+    \terminal{\# define } identifier lparen identifier-list \terminal{, ... )} replacement-list new-line\br
+\end{bnf}
+
+\begin{bnf}
+\nontermdef{undef-directive}\br
+    \terminal{\# undef \ } identifier new-line\br
+\end{bnf}
+
+\begin{bnf}
+\nontermdef{lparen}\br
+    \descr{a \terminal{(} character not immediately preceded by whitespace}
+\end{bnf}
+
+\begin{bnf}
+\nontermdef{identifier-list}\br
+    identifier\br
+    identifier-list \terminal{,} identifier
+\end{bnf}
+
+\begin{bnf}
+\nontermdef{replacement-list}\br
+    \opt{pp-tokens}
+\end{bnf}
+
 \pnum
 \indextext{macro!replacement list}%
 Two replacement lists are identical if and only if