/*
 *  call-seq:
 *    e.each_slice(n) {...}
 *
 *  Iterates the given block for each slice of <n> elements.
 *
 *  e.g.:
 *      (1..10).each_slice(3) {|a| p a}
 *      # outputs below
 *      [1, 2, 3]
 *      [4, 5, 6]
 *      [7, 8, 9]
 *      [10]
 *
 */
static VALUE
enum_each_slice(obj, n)
    VALUE obj, n;
{
    long size = NUM2LONG(n);
    NODE *memo;
    VALUE ary;

    if (size <= 0) rb_raise(rb_eArgError, "invalid slice size");

    memo = rb_node_newnode(NODE_MEMO, rb_ary_new2(size), 0, size);

    rb_iterate(rb_each, obj, each_slice_i, (VALUE)memo);

    ary = memo->u1.value;
    if (RARRAY(ary)->len > 0) rb_yield(ary);

    return Qnil;
}