Avoid usage of the magic number `(NODE*)-1`

This magic number has two meanings depending upon the context:

* "required keyword argument (no name)" on NODE_LASGN (`def foo(x:)`)
* "rest argument (no name)" on NODE_MASGN and NODE_POSTARG
  ('a, b, * = ary` or `a, b, *, z = ary`)

To show this intention explicitly, two macros are introduced:
NODE_SPECIAL_REQUIRED_KEYWORD and NODE_SPECIAL_NO_NAME_REST.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@60650 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

1 files changed, 3 insertions, 0 deletions

diff --git a/node.h b/node.h
index 848ef1b76e..d85f86746a 100644
--- a/node.h
+++ b/node.h
@@ -445,6 +445,9 @@ typedef struct RNode {
 #define NEW_ATTRASGN(r,m,a) NEW_NODE(NODE_ATTRASGN,r,m,a)
 #define NEW_PRELUDE(p,b,o) NEW_NODE(NODE_PRELUDE,p,b,o)
 
+#define NODE_SPECIAL_REQUIRED_KEYWORD ((NODE *)-1)
+#define NODE_SPECIAL_NO_NAME_REST     ((NODE *)-1)
+
 RUBY_SYMBOL_EXPORT_BEGIN
 
 typedef struct node_buffer_struct node_buffer_t;