From: nobu@...
Date: 2015-06-29T05:05:32+00:00
Subject: [ruby-core:69767] [Ruby trunk - Feature #11315] [PATCH] Add Array#^ for parity with other set-like operations.

Issue #11315 has been updated by Nobuyoshi Nakada.


`st_update` does lookup/replace/delete/insert in the callback at once.
And your patches are broken, necessary spaces are stripped.

~~~diff
diff --git a/array.c b/array.c
index 072e30d..737afa3 100644
--- a/array.c
+++ b/array.c
@@ -4200,6 +4200,14 @@ rb_ary_or(VALUE ary1, VALUE ary2)
     return ary3;
 }
 
+static int
+ary_hash_xorset(st_data_t *key, st_data_t *value, st_data_t arg, int existing)
+{
+    if (existing) return ST_DELETE;
+    *key = *value = (VALUE)arg;
+    return ST_CONTINUE;
+}
+
 /*
  *  call-seq:
  *     ary ^ other_ary     -> new_ary
@@ -4228,15 +4236,9 @@ rb_ary_xor(VALUE ary1, VALUE ary2)
     result = ary_make_hash(ary1);
 
     for (i = 0; i < RARRAY_LEN(ary2); ++i) {
-    elt = (st_data_t)RARRAY_AREF(ary2, i);
-    if (st_lookup(RHASH_TBL_RAW(seen), elt, 0)) continue;
-    st_update(RHASH_TBL_RAW(seen), elt, ary_hash_orset, elt);
-    if (st_lookup(RHASH_TBL_RAW(result), elt, 0)) {
-        st_delete(RHASH_TBL_RAW(result), &elt, 0);
-    }
-    else {
-        st_update(RHASH_TBL_RAW(result), elt, ary_hash_orset, elt);
-    }
+	elt = (st_data_t)RARRAY_AREF(ary2, i);
+	if (!st_update(RHASH_TBL_RAW(seen), elt, ary_hash_orset, elt))
+	    st_update(RHASH_TBL_RAW(result), elt, ary_hash_xorset, elt);
     }
 
     ary3 = rb_hash_values(result);
~~~

----------------------------------------
Feature #11315: [PATCH] Add Array#^ for parity with other set-like operations.
https://bugs.ruby-lang.org/issues/11315#change-53143

* Author: D.E. Akers
* Status: Open
* Priority: Normal
* Assignee: 
----------------------------------------
## Proposal

It is proposed that `Array` be given an "XOR" method which returns the symmetric difference between itself and another array.

## Rationale

`#&` and `#|` need a friend to complete the set of set-like operations on `Array`.

---Files--------------------------------
array_xor.patch (2.69 KB)
array_xor_vodka.patch (2.97 KB)
array_xor_recycle_seen.patch (3 KB)


-- 
https://bugs.ruby-lang.org/