fix Issue 9503 - [grammar] template declaration/instance must take on…

…e or more arguments?

- Define TemplateParameters and TemplateArguments, and use them as like Parameters
- Function template and template constructor also couldn't take zero template parameters.
  Moreover, DeclarationSuffix had been wrong, because TemplateParameterList does not have both side parenthesis.

declaration.dd

@@ -101,7 +101,7 @@ $(GNAME DeclaratorSuffix):
     $(D [ ])
     $(D [) $(VEXPRESSION) $(D ])
     $(D [) $(GLINK Type) $(D ])
-    $(GLINK2 template, TemplateParameterList)$(OPT) $(GLINK Parameters) $(GLINK MemberFunctionAttributes)$(OPT) $(GLINK2 template, Constraint)$(OPT)
+    $(GLINK2 template, TemplateParameters)$(OPT) $(GLINK Parameters) $(GLINK MemberFunctionAttributes)$(OPT) $(GLINK2 template, Constraint)$(OPT)
 
 $(GNAME IdentifierList):
     $(I Identifier)

template-mixin.dd

@@ -8,14 +8,14 @@ $(SPEC_S Template Mixins,
 
 $(GRAMMAR
 $(GNAME TemplateMixinDeclaration):
-    $(B mixin) $(B template) $(TEMPLATEIDENTIFIER) $(B $(LPAREN)) $(TEMPLATEPARAMETERLIST) $(B $(RPAREN)) $(V2 $(GLINK2 template, Constraint)$(OPT))
+    $(B mixin) $(B template) $(TEMPLATEIDENTIFIER) $(TEMPLATEPARAMETERS) $(V2 $(GLINK2 template, Constraint)$(OPT))
             $(B {) $(GLINK2 module, DeclDefs) $(B })
 
 $(GNAME TemplateMixin):
     $(B mixin) $(TEMPLATEIDENTIFIER) $(B ;)
     $(B mixin) $(TEMPLATEIDENTIFIER) $(GLINK MixinIdentifier) $(B ;)
-    $(B mixin) $(TEMPLATEIDENTIFIER) $(B !$(LPAREN)) $(TEMPLATEARGUMENTLIST) $(B $(RPAREN)) $(B ;)
-    $(B mixin) $(TEMPLATEIDENTIFIER) $(B !$(LPAREN)) $(TEMPLATEARGUMENTLIST) $(B $(RPAREN)) $(GLINK MixinIdentifier) $(B ;)
+    $(B mixin) $(TEMPLATEIDENTIFIER) $(TEMPLATEARGUMENTS) $(B ;)
+    $(B mixin) $(TEMPLATEIDENTIFIER) $(TEMPLATEARGUMENTS) $(GLINK MixinIdentifier) $(B ;)
 
 $(GNAME MixinIdentifier):
     $(I Identifier)
@@ -306,6 +306,6 @@ Macros:
         WIKI=Mixin
         CATEGORY_SPEC=$0
         TEMPLATEIDENTIFIER=$(GLINK2 template, TemplateIdentifier)
-        TEMPLATEPARAMETERLIST=$(GLINK2 template, TemplateParameterList)
-        TEMPLATEARGUMENTLIST=$(GLINK2 template, TemplateArgumentList)
+        TEMPLATEPARAMETERS=$(GLINK2 template, TemplateParameters)
+        TEMPLATEARGUMENTS=$(GLINK2 template, TemplateArguments)
         FOO=

template.dd

@@ -12,12 +12,16 @@ $(P     Templates are D's approach to generic programming.
 
 $(GRAMMAR
 $(GNAME TemplateDeclaration):
-    $(B template) $(GLINK TemplateIdentifier) $(B $(LPAREN)) $(GLINK TemplateParameterList) $(B $(RPAREN)) $(GLINK Constraint)$(OPT)
+    $(B template) $(GLINK TemplateIdentifier) $(GLINK TemplateParameters) $(GLINK Constraint)$(OPT)
             $(B {) $(GLINK2 module, DeclDefs) $(B })
 
 $(GNAME TemplateIdentifier):
     $(I Identifier)
 
+$(GNAME TemplateParameters):
+    $(B $(LPAREN) $(RPAREN))
+    $(B $(LPAREN)) $(GLINK TemplateParameterList) $(B $(RPAREN))
+
 $(GNAME TemplateParameterList):
     $(GLINK TemplateParameter)
     $(GLINK TemplateParameter) ,
@@ -65,8 +69,12 @@ $(P
 
 $(GRAMMAR
 $(GNAME TemplateInstance):
-    $(GLINK TemplateIdentifier) $(B !$(LPAREN)) $(GLINK TemplateArgumentList) $(B $(RPAREN))
-    $(GLINK TemplateIdentifier) $(B !) $(GLINK TemplateSingleArgument)
+    $(GLINK TemplateIdentifier) $(GLINK TemplateArguments)
+
+$(GNAME TemplateArguments):
+    $(B !$(LPAREN) $(RPAREN))
+    $(B !$(LPAREN)) $(GLINK TemplateArgumentList) $(B $(RPAREN))
+    $(B !) $(GLINK TemplateSingleArgument)
 
 $(GNAME TemplateArgumentList):
     $(GLINK TemplateArgument)
@@ -747,7 +755,7 @@ $(H2 Template Constructors)
 
 $(GRAMMAR
 $(GNAME TemplatedConstructor):
-    $(B this) $(B $(LPAREN)) $(GLINK2 template, TemplateParameterList) $(B $(RPAREN)) $(GLINK2 declaration, Parameters) $(GLINK Constraint)$(OPT) $(GLINK2 function, FunctionBody)
+    $(B this) $(GLINK2 template, TemplateParameters) $(GLINK2 declaration, Parameters) $(GLINK Constraint)$(OPT) $(GLINK2 function, FunctionBody)
 )
 
         $(P Templates can be used to form constructors for classes  and structs.