src/HOLCF/Ssum1.ML

         THEN (atac 2)
         THEN (etac sym 1));
 
 Goalw [less_ssum_def]
 "[|s1=Isinl(x::'a); s2=Isinl(y::'a)|] ==> s1 << s2 = (x << y)";
-by (rtac select_equality 1);
+by (rtac some_equality 1);
 by (dtac conjunct1 2);
 by (dtac spec 2);
 by (dtac spec 2);
 by (etac mp 2);
 by (fast_tac HOL_cs 2);

 qed "less_ssum1a";
 
 
 Goalw [less_ssum_def]
 "[|s1=Isinr(x::'b); s2=Isinr(y::'b)|] ==> s1 << s2 = (x << y)";
-by (rtac select_equality 1);
+by (rtac some_equality 1);
 by (dtac conjunct2 2);
 by (dtac conjunct1 2);
 by (dtac spec 2);
 by (dtac spec 2);
 by (etac mp 2);

 qed "less_ssum1b";
 
 
 Goalw [less_ssum_def]
 "[|s1=Isinl(x::'a); s2=Isinr(y::'b)|] ==> s1 << s2 = ((x::'a) = UU)";
-by (rtac select_equality 1);
+by (rtac some_equality 1);
 by (rtac conjI 1);
 by (strip_tac 1);
 by (etac conjE 1);
 by (eq_left  "x" "u");
 by (UU_left "xa");

 qed "less_ssum1c";
 
 
 Goalw [less_ssum_def]
 "[|s1=Isinr(x); s2=Isinl(y)|] ==> s1 << s2 = (x = UU)";
-by (rtac select_equality 1);
+by (rtac some_equality 1);
 by (dtac conjunct2 2);
 by (dtac conjunct2 2);
 by (dtac conjunct2 2);
 by (dtac spec 2);
 by (dtac spec 2);