+- allow __ at the beginning of a struct or union name
+- unparsing with precedence
+- Type metavariable should not match a case where there is no type in the
+ C code. Thanks to SF Markus Elfring for pointing out the problem.
+- Allow an expression list metavariable to be attached to a parameter list
+ metavariable, to allow using the parameter names as an argument list.
+ Thanks to Michael Stefaniuc for pointing out the need for this feature.