==================
Lambda Abstraction
==================

foo := fun (A : *) (x : A) => x;

----------

(program
  (definition
    (identifier)
    (expr
      (app_term
        (labs
          (lambda)
          (param_block
            (param
              (identifier))
            (type
              (expr
                (app_term
                  (app
                    (term
                      (star)))))))
          (param_block
            (param
              (identifier))
            (type
              (expr
                (app_term
                  (app
                    (term
                      (identifier)))))))
          (expr
            (app_term
              (app
                (term
                  (identifier))))))))))