root start
recursive start
value_a begin
value->constant
value: post_expression override
value_a: post_value override
value_a end
recursive->expression event
recursive start
value_b begin
value->constant
value: post_expression override
value_b: post_value override
value_b end
recursive->expression event
recursive: post_expression override
recursive end
recursive->expression event
recursive: post_expression override
recursive end
root->expression
root end
