src/Pure/envir.ML
1994-11-21 lcp 1994-11-21 Pure/envir/norm_term: replaced equality test for [] by null
1994-01-24 wenzelm 1994-01-24 added is_empty: env -> bool, minidx: env -> int option;
1993-09-16 clasohm 1993-09-16 Initial revision