Method: Enumerator#feed

Defined in:

enumerator.c

#obj ⇒ nil

Set the value for the next yield in the enumerator returns.

If the value is not set, the yield returns nil.

This value is cleared after used.

o = Object.new
def o.each
  # (2)
  x = yield
  p x          #=> "foo"
  # (5)
  x = yield
  p x          #=> nil
  # (7)
  x = yield
  # not reached
  p x
end
e = o.to_enum
# (1)
e.next
# (3)
e.feed "foo"
# (4)
e.next
# (6)
e.next
# (8)

Returns:

• (nil)

# File 'enumerator.c'

/*
 * call-seq:
 *   e.feed obj   -> nil
 *
 * Set the value for the next yield in the enumerator returns.
 *
 * If the value is not set, the yield returns nil.
 *
 * This value is cleared after used.
 *
 *   o = Object.new
 *   def o.each
 *     # (2)
 *     x = yield
 *     p x          #=> "foo"
 *     # (5)
 *     x = yield
 *     p x          #=> nil
 *     # (7)
 *     x = yield
 *     # not reached
 *     p x
 *   end
 *   e = o.to_enum
 *   # (1)
 *   e.next
 *   # (3)
 *   e.feed "foo"
 *   # (4)
 *   e.next
 *   # (6)
 *   e.next
 *   # (8)
 *
 */

static VALUE
enumerator_feed(VALUE obj, VALUE v)
{
    struct enumerator *e = enumerator_ptr(obj);

    if (e->feedvalue != Qundef) {
    rb_raise(rb_eTypeError, "feed value already set");
    }
    e->feedvalue = v;

    return Qnil;
}