(*  -*- isa -*-

    Example proof script for Isabelle Proof General.

    Example.ML,v 8.0 2004/04/17 23:40:00 da Exp

    The line at the top of this comment forces 
    Proof General's classic Isabelle mode
    (instead of Isar: you can't use both at once).
*)

Goal "A & B --> B & A";
  by (rtac impI 1);
  by (etac conjE 1);
  by (rtac conjI 1);
  by (assume_tac 1);
  by (assume_tac 1);
qed "and_comms";
