diff options
| -rw-r--r-- | lib.c | 30 | ||||
| -rw-r--r-- | txr.1 | 5 |
2 files changed, 32 insertions, 3 deletions
@@ -10628,13 +10628,37 @@ static val do_relate_dfl(val env, val arg) return if3(pos, ref(rng, pos), dfl); } +static val do_relate_hash(val hash, val arg) +{ + val cell = gethash_e(lit("relate"), hash, arg); + return if3(cell, cdr(cell), arg); +} + +static val do_relate_hash_dfl(val env, val arg) +{ + cons_bind (hash, dfl, env); + val cell = gethash_e(lit("relate"), hash, arg); + return if3(cell, cdr(cell), dfl); +} val relate(val domain_seq, val range_seq, val dfl_val) { + val lds = length(domain_seq); + val use_hash = and2(gt(lds, num_fast(10)), + le(lds, length(range_seq))); + args_decl(args, ARGS_MIN); + val hash = if2(use_hash, hash_zip(domain_seq, range_seq, args)); + return if3(missingp(dfl_val), - func_f1(cons(domain_seq, range_seq), do_relate), - func_f1(vec(domain_seq, range_seq, dfl_val, nao), - do_relate_dfl)); + if3(use_hash, + func_f1(hash, do_relate_hash), + func_f1(cons(domain_seq, range_seq), do_relate)), + if3(use_hash, + if3(null(dfl_val), + hash, + func_f1(cons(hash, dfl_val), do_relate_hash_dfl)), + func_f1(vec(domain_seq, range_seq, dfl_val, nao), + do_relate_dfl))); } val rcons(val from, val to) @@ -29753,6 +29753,11 @@ function may be understood in terms of the following equivalences: v)) .brev +Note: +.code relate +may return a hash table instead of a function, if such an object +can satisfy the semantics required by the arguments. + .TP* Examples: .verb |