[dcl.fct] Split and reorder productions for parameter-declaration-clause

Author: eisenwave

source/declarations.tex

@@ -3602,8 +3602,10 @@
 \indextext{declaration!function}%
 \begin{bnf}
 \nontermdef{parameter-declaration-clause}\br
-    \opt{parameter-declaration-list} \opt{\terminal{...}}\br
-    parameter-declaration-list \terminal{,} \terminal{...}
+    \terminal{...}\br
+    \opt{parameter-declaration-list}\br
+    parameter-declaration-list \terminal{,} \terminal{...}\br
+    parameter-declaration-list \terminal{...}
 \end{bnf}
 
 \begin{bnf}