Add member access operators

grammar.coffee

@@ -34,7 +34,20 @@ module.exports = compiler.grammar
       @undefined,
       @object,
       @array,
-      @function)
+      @function,
+      @member_access,
+      @subscript_access)
+
+    member_access: -> seq(
+      @expression,
+      ".",
+      @identifier)
+
+    subscript_access: -> seq(
+      @expression,
+      "[",
+      @expression,
+      "]")
 
     object: -> seq(
       "{",

grammar_test/expressions.txt

@@ -122,3 +122,19 @@ function(arg1, arg2) {
     (formal_parameters (identifier) (identifier))
     (statement_block
       (expression_statement (identifier))))))
+
+============================================
+Property access
+============================================
+
+x.someProperty;
+x[someVariable];
+x["some-string"];
+
+---
+
+(program
+  (expression_statement (member_access (identifier) (identifier)))
+  (expression_statement (subscript_access (identifier) (identifier)))
+  (expression_statement (subscript_access (identifier) (string))))
+