Document Placement NewExpression

Author: WalterBright

spec/class.dd

@@ -1439,7 +1439,7 @@ $(H3 $(LNAME2 anonymous, Anonymous Nested Classes))
 
 $(GRAMMAR
 $(GNAME NewAnonClassExpression):
-    $(D new) $(D class) $(GLINK ConstructorArgs)$(OPT) $(GLINK AnonBaseClassList)$(OPT) $(GLINK2 struct, AggregateBody)
+    $(D new) $(GLINK2 expression, PlacementExpression)$(OPT) $(D class) $(GLINK ConstructorArgs)$(OPT) $(GLINK AnonBaseClassList)$(OPT) $(GLINK2 struct, AggregateBody)
 
 $(GNAME ConstructorArgs):
     $(D $(LPAREN)) $(GLINK2 expression, NamedArgumentList)$(OPT) $(D $(RPAREN))

spec/expression.dd

@@ -2920,15 +2920,18 @@ $(H3 $(LNAME2 new_expressions, New Expressions))
 
 $(GRAMMAR
 $(GNAME NewExpression):
-    $(D new) $(GLINK2 type, Type)
-    $(D new) $(GLINK2 type, Type) $(D [) $(GLINK AssignExpression) $(D ])
-    $(D new) $(GLINK2 type, Type) $(D $(LPAREN)) $(GLINK NamedArgumentList)$(OPT) $(D $(RPAREN))
+    $(D new) $(GLINK PlacementExpression)$(OPT) $(GLINK2 type, Type)
+    $(D new) $(GLINK PlacementExpression)$(OPT) $(GLINK2 type, Type) $(D [) $(GLINK AssignExpression) $(D ])
+    $(D new) $(GLINK PlacementExpression)$(OPT) $(GLINK2 type, Type) $(D $(LPAREN)) $(GLINK NamedArgumentList)$(OPT) $(D $(RPAREN))
     $(GLINK2 class, NewAnonClassExpression)
+
+$(GNAME PlacementExpression):
+    $(LPAREN) $(GLINK AssignExpression) $(RPAREN)
 )
 
     $(P $(I NewExpression)s allocate memory on the
         $(DDLINK spec/garbage, Garbage Collection, garbage
-        collected) heap by default.
+        collected) heap unless there is a $(RELATIVE_LINK2 PlacementExpression, PlacementExpression).
     )
 
     $(P `new T` constructs an instance of type `T` and default-initializes it.
@@ -3037,6 +3040,8 @@ $(H4 $(LNAME2 new_multidimensional, Multidimensional Arrays))
         }
         -----------
 
+$(H4 $(LNAME2 PlacementExpression, Placement Expression))
+
 $(H3 $(LNAME2 typeid_expressions, Typeid Expressions))
 
 $(GRAMMAR