Reclaim alternative names for users, closes #328

Another thing there's no need to support anymore and that we shouldn't have to teach... these haven't been needed since the 1980s.

Normally we don't have to teach things that compilers treat as errors, because they don't compile, but this is a case where the error is surprising and so we still have to teach it (i.e., when users trip across trying to use a common word like `and` as a variable name and wonder why it's an error and then it's a whole thing again)

Author: hsutter

source/cppfront.cpp

@@ -1447,12 +1447,31 @@ class cppfront
 
         declaration_node const* decl = {};
 
+        //  'new' is a named allocator object
         if (n == "new") {
             printer.print_cpp2("cpp2_new", pos);
         }
+        //  'this' is not a pointer
         else if (n == "this") {
             printer.print_cpp2("(*this)", pos);
         }
+        //  Reclaim the alternative names for users
+        else if (
+            n == "and"
+            || n == "and_eq"
+            || n == "bitand"
+            || n == "bitor"
+            || n == "compl"
+            || n == "not"
+            || n == "not_eq"
+            || n == "or_eq"
+            || n == "or_eq"
+            || n == "xor"
+            || n == "xor_eq"
+            )
+        {
+            printer.print_cpp2(n.to_string(true) + "_", pos);
+        }
         else if (
             current_declarations.back()
             && (decl = current_declarations.back()->get_decl_if_type_scope_object_name_before_a_base_type(n))