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authorKaz Kylheku <kaz@kylheku.com>2017-11-16 06:38:49 -0800
committerKaz Kylheku <kaz@kylheku.com>2017-11-16 06:38:49 -0800
commit6570b4ba2056818462a01f2752f318cc00e0e8da (patch)
treee24d6778ea173afd3ef4a9af0ff530c9c2e27410
parent89b51ce4482c0d10abe2947fb02876784119e091 (diff)
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pos-max: rewrite.
* lib.c (pos_max): Rewrite using seq_info.
-rw-r--r--lib.c66
1 files changed, 48 insertions, 18 deletions
diff --git a/lib.c b/lib.c
index cfd538df..27886684 100644
--- a/lib.c
+++ b/lib.c
@@ -8951,32 +8951,62 @@ val rpos_if(val pred, val seq, val key)
val pos_max(val seq, val testfun, val keyfun)
{
- val pos = zero;
- val maxkey;
- val maxpos = zero;
-
- seq = nullify(seq);
+ seq_info_t si = seq_info(seq);
+ testfun = default_arg(testfun, greater_f);
+ keyfun = default_arg(keyfun, identity_f);
- if (!seq)
+ switch (si.kind) {
+ case SEQ_NIL:
return nil;
+ case SEQ_LISTLIKE:
+ {
+ val maxkey = funcall1(keyfun, car(si.obj));
+ val maxpos = zero;
+ val pos;
- gc_hint(seq);
+ gc_hint(seq);
- testfun = default_arg(testfun, greater_f);
- keyfun = default_arg(keyfun, identity_f);
+ for (pos = one, seq = cdr(z(si.obj));
+ seq;
+ seq = cdr(seq), pos = succ(pos))
+ {
+ val elt = car(seq);
+ val key = funcall1(keyfun, elt);
+ if (funcall2(testfun, key, maxkey)) {
+ maxkey = key;
+ maxpos = pos;
+ }
+ }
- maxkey = funcall1(keyfun, car(seq));
+ return maxpos;
+ }
+ case SEQ_VECLIKE:
+ {
+ val vec = si.obj;
+ val len = length(vec);
- for (seq = cdr(seq); seq; seq = cdr(seq)) {
- val key = funcall1(keyfun, car(seq));
- pos = plus(pos, one);
- if (funcall2(testfun, key, maxkey)) {
- maxkey = key;
- maxpos = pos;
+ if (len != zero) {
+ val maxpos = zero;
+ val maxkey = funcall1(keyfun, ref(vec, zero));
+ val i;
+
+ for (i = one; lt(i, len); i = succ(i)) {
+ val elt = ref(vec, i);
+ val key = funcall1(keyfun, elt);
+ if (funcall2(testfun, key, maxkey)) {
+ maxkey = key;
+ maxpos = i;
+ }
+ }
+ return maxpos;
+ }
+
+ return nil;
}
+ case SEQ_NOTSEQ:
+ default:
+ uw_throwf(error_s, lit("pos-max: unsupported object ~s"), seq, nao);
}
-
- return maxpos;
}
val pos_min(val seq, val testfun, val keyfun)