New function: search-all

* eval.c (eval_init): search-all intrinsic registered.

* lib.c (search_common): New Boolean argument all,
indicating whether all positions are to be returned.
We must handle this in the two places where empty
key and sequence are handled, and also in the main loop.
A trick is used: the found variable is now bound by
list_collect_decl, but not used for collecting unless
all is true.
(search, rsearch, contains): Pass 0 for all argument
of search_common.
(search_all): New function.

* lib.h (search_all): Declared.

* tests/012/seq.tl: New tests.

* txr.1: Documented.

* stdlib/doc-syms.tl: Regenerated.

1 files changed, 28 insertions, 9 deletions

diff --git a/lib.c b/lib.c
index b6b94ebb..13ac61ad 100644
--- a/lib.c
+++ b/lib.c
@@ -12763,7 +12763,7 @@ val update(val seq, val fun)
   return seq;
 }
 
-static val search_common(val self, int from_right,
+static val search_common(val self, int all, int from_right,
                          val seq, val key, val testfun_in, val keyfun_in)
 {
   val testfun = default_arg(testfun_in, equal_f);
@@ -12774,17 +12774,29 @@ static val search_common(val self, int from_right,
   seq_iter_init(self, &ki, key);
 
   if (si.inf.kind == SEQ_NIL) {
-    return if3(length(key) == zero, zero, nil);
+    val kelem;
+    return if2(!seq_peek(&ki, &kelem),
+               if3(all, cons(zero, nil), zero));
   } else if (ki.inf.kind == SEQ_HASHLIKE || si.inf.kind == SEQ_HASHLIKE) {
     type_mismatch(lit("~a: hashes not supported"), self, nao);
-  } else if (ki.inf.kind == SEQ_NIL) {
+  } else if (!all && ki.inf.kind == SEQ_NIL) {
     return if3(from_right, length(seq), zero);
   } else {
     val selem, kelem;
-    val pos = zero, found = nil;
+    val pos = zero;
+    list_collect_decl (found, ptail);
 
-    if (!seq_peek(&ki, &kelem))
+    if (!seq_peek(&ki, &kelem)) {
+      if (all) {
+        while (seq_get(&si, &selem)) {
+          ptail = list_collect(ptail, pos);
+          pos = plus(pos, one);
+        }
+        list_collect(ptail, pos);
+        return found;
+      }
       return if3(from_right, length(seq), zero);
+    }
 
     for (;;) {
       val did_save = nil;
@@ -12816,7 +12828,9 @@ static val search_common(val self, int from_right,
       }
 
       if (!more_key) {
-        if (from_right)
+        if (all)
+          ptail = list_collect(ptail, pos);
+        else if (from_right)
           found = pos;
         else
           return pos;
@@ -12834,17 +12848,22 @@ static val search_common(val self, int from_right,
 
 val search(val seq, val key, val testfun, val keyfun)
 {
-  return search_common(lit("search"), 0, seq, key, testfun, keyfun);
+  return search_common(lit("search"), 0, 0, seq, key, testfun, keyfun);
 }
 
 val rsearch(val seq, val key, val testfun, val keyfun)
 {
-  return search_common(lit("rsearch"), 1, seq, key, testfun, keyfun);
+  return search_common(lit("rsearch"), 0, 1, seq, key, testfun, keyfun);
 }
 
 val contains(val key, val seq, val testfun, val keyfun)
 {
-  return search_common(lit("contains"), 0, seq, key, testfun, keyfun);
+  return search_common(lit("contains"), 0, 0, seq, key, testfun, keyfun);
+}
+
+val search_all(val seq, val key, val testfun, val keyfun)
+{
+  return search_common(lit("search-all"), 1, 0, seq, key, testfun, keyfun);
 }
 
 static val lazy_where_func(val iter, val lcons)