new meta-rule "inst", a shorthand for read_instantiate_sg
authorpaulson
Wed, 22 Mar 2000 12:33:34 +0100
changeset 8550 b44c185f8018
parent 8549 851d39c10d9f
child 8551 5c22595bc599
new meta-rule "inst", a shorthand for read_instantiate_sg
src/Pure/drule.ML
--- a/src/Pure/drule.ML	Tue Mar 21 17:43:54 2000 +0100
+++ b/src/Pure/drule.ML	Wed Mar 22 12:33:34 2000 +0100
@@ -76,6 +76,7 @@
   val triv_forall_equality: thm
   val swap_prems_rl     : thm
   val equal_intr_rule   : thm
+  val inst              : string -> string -> thm -> thm
   val instantiate'      : ctyp option list -> cterm option list -> thm -> thm
   val incr_indexes      : int -> thm -> thm
   val incr_indexes_wrt  : int list -> ctyp list -> cterm list -> thm list -> thm -> thm
@@ -629,6 +630,10 @@
 
 (** variations on instantiate **)
 
+(*shorthand for instantiating just one variable in the current theory*)
+fun inst x t = read_instantiate_sg (sign_of (the_context())) [(x,t)];
+
+
 (* collect vars *)
 
 val add_tvarsT = foldl_atyps (fn (vs, TVar v) => v ins vs | (vs, _) => vs);