spec: Add EmptyDeclaration and EmptyStatement

CyberShadow · Geod24 · commit 09c26995fde4 · 2021-07-05T13:46:43.000+09:00
- Semantically indicate that the various occurrences of $(D ;) all
  mean the same thing

- Add explicit counterpart to e.g. NonEmptyStatement

- Avoiding mixing leaf and non-leaf nodes makes the grammar more
  structured in general.
diff --git a/spec/module.dd b/spec/module.dd
@@ -37,6 +37,9 @@ $(GNAME DeclDef):
     $(GLINK2 template-mixin, TemplateMixinDeclaration)
     $(GLINK2 template-mixin, TemplateMixin)
     $(GLINK MixinDeclaration)
+    $(GLINK EmptyDeclaration)
+
+$(GNAME EmptyDeclaration):
     $(D ;)
 )
 
diff --git a/spec/statement.dd b/spec/statement.dd
@@ -12,16 +12,19 @@ $(HEADERNAV_TOC)
 
 $(GRAMMAR
 $(GNAME Statement):
-    $(D ;)
+    $(GLINK EmptyStatement)
     $(GLINK NonEmptyStatement)
     $(GLINK ScopeBlockStatement)
 
+$(GNAME EmptyStatement):
+    $(D ;)
+
 $(GNAME NoScopeNonEmptyStatement):
     $(GLINK NonEmptyStatement)
     $(GLINK BlockStatement)
 
 $(GNAME NoScopeStatement):
-    $(D ;)
+    $(GLINK EmptyStatement)
     $(GLINK NonEmptyStatement)
     $(GLINK BlockStatement)
 
@@ -1095,7 +1098,7 @@ $(GNAME StatementListNoCaseNoDefault):
     $(GLINK StatementNoCaseNoDefault) $(GSELF StatementListNoCaseNoDefault)
 
 $(GNAME StatementNoCaseNoDefault):
-    $(D ;)
+    $(GLINK EmptyStatement)
     $(GLINK NonEmptyStatementNoCaseNoDefault)
     $(GLINK ScopeBlockStatement)
 )

Original file line number	Diff line number	Diff line change
`@@ -37,6 +37,9 @@ $(GNAME DeclDef):`
`37`	`37`	`$(GLINK2 template-mixin, TemplateMixinDeclaration)`
`38`	`38`	`$(GLINK2 template-mixin, TemplateMixin)`
`39`	`39`	`$(GLINK MixinDeclaration)`
	`40`	`+ $(GLINK EmptyDeclaration)`
	`41`	`+`
	`42`	`+$(GNAME EmptyDeclaration):`
`40`	`43`	`$(D ;)`
`41`	`44`	`)`
`42`	`45`