# HG changeset patch
# User blanchet
# Date 1416828913 -3600
# Node ID ef0074e812cd606a9f2574fc765fd5263622bf70
# Parent  2a23235632b207a3b5796aeb8afc709b6208ca6a
smoothly handle unit codatatypes in 'primcorec'

diff -r 2a23235632b2 -r ef0074e812cd src/HOL/Tools/BNF/bnf_gfp_rec_sugar.ML
--- a/src/HOL/Tools/BNF/bnf_gfp_rec_sugar.ML	Mon Nov 24 12:35:13 2014 +0100
+++ b/src/HOL/Tools/BNF/bnf_gfp_rec_sugar.ML	Mon Nov 24 12:35:13 2014 +0100
@@ -696,7 +696,7 @@
 
     val disc_concl = betapply (disc, lhs);
     val (eqn_data_disc_opt, matchedsss') =
-      if null (tl basic_ctr_specs) then
+      if null (tl basic_ctr_specs) andalso not (null sels) then
         (NONE, matchedsss)
       else
         apfst SOME (dissect_coeqn_disc lthy fun_names sequentials basic_ctr_specss eqn_pos