Allow pointer types in typedefs

grammar.coffee

@@ -45,7 +45,7 @@ module.exports = grammar
     typedef: -> seq(
       keyword("typedef"),
       @type,
-      @identifier,
+      @type_expression,
       ";")
 
     var_declaration: -> seq(

grammar_test/declarations.txt

@@ -110,9 +110,17 @@ Typedefs
 
 typedef int my_int;
 
+typedef struct{
+  int x;
+} *a;
+
 ---
 
-(typedef (identifier) (identifier))
+(program
+  (typedef (identifier) (identifier))
+  (typedef (struct_type
+    (field (identifier) (identifier)))
+    (pointer_type (identifier))))
 
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 Function declarations