* st.c (st_keys): define st_keys() for performance improvement of

  Hash#keys and Array#uniq.

* st.h: ditto.

* hash.c (rb_hash_keys): use st_keys().

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@43238 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

1 files changed, 31 insertions, 0 deletions

diff --git a/st.c b/st.c
index 6e3df628a7..43e2d71d24 100644
--- a/st.c
+++ b/st.c
@@ -1091,6 +1091,37 @@ st_foreach(st_table *table, int (*func)(ANYARGS), st_data_t arg)
     return 0;
 }
 
+VALUE
+st_keys(st_table *table)
+{
+    st_table_entry *ptr = NULL;
+    st_data_t key, never = (st_data_t)Qundef;
+    VALUE keys = rb_ary_new_capa(table->num_entries);
+
+    if (table->entries_packed) {
+	st_index_t i;
+
+	for (i = 0; i < table->real_entries; i++) {
+	    key = PKEY(table, i);
+	    if (key == never) continue;
+	    rb_ary_push(keys, (VALUE)key);
+	}
+    }
+    else {
+	ptr = table->head;
+    }
+
+    if (ptr != 0) {
+	do {
+	    key = ptr->key;
+	    if (key != never) rb_ary_push(keys, (VALUE)key);
+	    ptr = ptr->fore;
+	} while (ptr && table->head);
+    }
+
+    return keys;
+}
+
 #if 0  /* unused right now */
 int
 st_reverse_foreach(st_table *table, int (*func)(ANYARGS), st_data_t arg)