* enum.c (enum_zip): honor length of the receiver, not the

  shortest length.  [ruby-core:14738]

* enum.c (enum_zip): returns array not enumerator for no block
  form.  [ruby-core:14738]

* enumerator.c (next_ii): do not ignore multiple values yielded.

* array.c (rb_ary_zip): faster version without creating generators.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@14952 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

1 files changed, 79 insertions, 0 deletions

diff --git a/array.c b/array.c
index c6ca7a8668..7c7fae0844 100644
--- a/array.c
+++ b/array.c
@@ -1983,6 +1983,84 @@ rb_ary_delete_if(VALUE ary)
     return ary;
 }
 
+static VALUE
+take_i(VALUE val, VALUE *args, int argc, VALUE *argv)
+{
+    if (args[1]-- == 0) rb_iter_break();
+    if (argc > 1) val = rb_ary_new4(argc, argv);
+    rb_ary_push(args[0], val);
+    return Qnil;
+}
+
+static VALUE
+take_items(VALUE obj, long n)
+{
+    VALUE result = rb_ary_new2(n);
+    VALUE args[2];
+
+    args[0] = result; args[1] = (VALUE)n;
+    rb_block_call(obj, rb_intern("each"), 0, 0, take_i, (VALUE)args);
+    return result;
+}
+
+
+/*
+ *  call-seq:
+ *     array.zip(arg, ...)                   -> an_array
+ *     array.zip(arg, ...) {| arr | block }  -> nil
+ *  
+ *  Converts any arguments to arrays, then merges elements of
+ *  <i>self</i> with corresponding elements from each argument. This
+ *  generates a sequence of <code>self.size</code> <em>n</em>-element
+ *  arrays, where <em>n</em> is one more that the count of arguments. If
+ *  the size of any argument is less than <code>enumObj.size</code>,
+ *  <code>nil</code> values are supplied. If a block given, it is
+ *  invoked for each output array, otherwise an array of arrays is
+ *  returned.
+ *     
+ *     a = [ 4, 5, 6 ]
+ *     b = [ 7, 8, 9 ]
+ *     
+ *     [1,2,3].zip(a, b)      #=> [[1, 4, 7], [2, 5, 8], [3, 6, 9]]
+ *     [1,2].zip(a,b)         #=> [[1, 4, 7], [2, 5, 8]]
+ *     a.zip([1,2],[8])       #=> [[4,1,8], [5,2,nil], [6,nil,nil]]
+ */
+
+static VALUE
+rb_ary_zip(argc, argv, ary)
+    int argc;
+    VALUE *argv;
+    VALUE ary;
+{
+    int i, j;
+    long len;
+    VALUE result = Qnil;
+
+    len = RARRAY_LEN(ary);
+    for (i=0; i<argc; i++) {
+	argv[i] = take_items(argv[i], len);
+    }
+    if (!rb_block_given_p()) {
+	result = rb_ary_new2(len);
+    }
+
+    for (i=0; i<RARRAY_LEN(ary); i++) {
+	VALUE tmp = rb_ary_new2(argc+1);
+
+	rb_ary_push(tmp, rb_ary_elt(ary, i));
+	for (j=0; j<argc; j++) {
+	    rb_ary_push(tmp, rb_ary_elt(argv[j], i));
+	}
+	if (NIL_P(result)) {
+	    rb_yield(tmp);
+	}
+	else {
+	    rb_ary_push(result, tmp);
+	}
+    }
+    return result;
+}
+
 /*
  *  call-seq:
  *     array.transpose -> an_array
@@ -3299,6 +3377,7 @@ Init_Array(void)
     rb_define_method(rb_cArray, "delete_if", rb_ary_delete_if, 0);
     rb_define_method(rb_cArray, "reject", rb_ary_reject, 0);
     rb_define_method(rb_cArray, "reject!", rb_ary_reject_bang, 0);
+    rb_define_method(rb_cArray, "zip", rb_ary_zip, -1);
     rb_define_method(rb_cArray, "transpose", rb_ary_transpose, 0);
     rb_define_method(rb_cArray, "replace", rb_ary_replace, 1);
     rb_define_method(rb_cArray, "clear", rb_ary_clear, 0);