thys/Spec.thy
changeset 287 95b3880d428f
parent 286 804fbb227568
child 289 807acaf7f599
equal deleted inserted replaced
286:804fbb227568 287:95b3880d428f
   172 lemma ders_correctness:
   172 lemma ders_correctness:
   173   shows "L (ders s r) = Ders s (L r)"
   173   shows "L (ders s r) = Ders s (L r)"
   174 by (induct s arbitrary: r)
   174 by (induct s arbitrary: r)
   175    (simp_all add: Ders_def der_correctness Der_def)
   175    (simp_all add: Ders_def der_correctness Der_def)
   176 
   176 
       
   177 lemma ders_append:
       
   178   shows "ders (s1 @ s2) r = ders s2 (ders s1 r)"
       
   179   apply(induct s1 arbitrary: s2 r)
       
   180   apply(auto)
       
   181   done
   177 
   182 
   178 
   183 
   179 section {* Values *}
   184 section {* Values *}
   180 
   185 
   181 datatype val = 
   186 datatype val =