id.def: $~ and $_

* defs/id.def (predefined): add idLASTLINE and idBACKREF for $~
  and $_ respectively.
* parse.y: use idLASTLINE and idBACKREF instead of rb_intern.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@53856 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

ChangeLog

@@ -1,3 +1,10 @@
+Wed Feb 17 21:41:29 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
+
+	* defs/id.def (predefined): add idLASTLINE and idBACKREF for $~
+	  and $_ respectively.
+
+	* parse.y: use idLASTLINE and idBACKREF instead of rb_intern.
+
 Wed Feb 17 20:23:38 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
 
 	* string.c (rb_str_init): fix segfault and memory leak, consider

defs/id.def

@@ -62,6 +62,9 @@ firstline, predefined = __LINE__+1, %[\
   core#hash_merge_kwd
 
   -                                                     debug#created_info
+
+  $_                                                    LASTLINE
+  $~                                                    BACKREF
 ]
 
 # VM ID         OP      Parser Token
@@ -145,7 +148,7 @@ predefined.split(/^/).each_with_index do |line, num|
   case name
   when /\A[A-Z]\w*\z/; const_ids
   when /\A(?!\d)\w+\z/; local_ids
-  when /\A\$(?:\d+|(?!\d)\w+)\z/; global_ids
+  when /\A\$(?:\d+|(?!\d)\w+|\W)\z/; global_ids
   when /\A@@(?!\d)\w+\z/; class_ids
   when /\A@(?!\d)\w+\z/; instance_ids
   when /\A((?!\d)\w+)=\z/; attrset_ids

parse.y

@@ -9887,7 +9887,7 @@ cond0(struct parser_params *parser, NODE *node)
       case NODE_DREGX:
       case NODE_DREGX_ONCE:
 	warning_unless_e_option(parser, node, "regex literal in condition");
-	return NEW_MATCH2(node, NEW_GVAR(rb_intern("$_")));
+	return NEW_MATCH2(node, NEW_GVAR(idLASTLINE));
 
       case NODE_AND:
       case NODE_OR:
@@ -10610,7 +10610,7 @@ reg_named_capture_assign_iter(const OnigUChar *name, const OnigUChar *name_end,
     arg->succ_block = block_append(arg->succ_block,
         newline_node(node_assign(assignable(var,0),
             NEW_CALL(
-              gettable(rb_intern("$~")),
+              gettable(idBACKREF),
               idAREF,
               NEW_LIST(NEW_LIT(ID2SYM(var))))
             )));
@@ -10637,12 +10637,12 @@ reg_named_capture_assign_gen(struct parser_params* parser, VALUE regexp, NODE *m
     return
         block_append(
             newline_node(match),
-            NEW_IF(gettable(rb_intern("$~")),
+            NEW_IF(gettable(idBACKREF),
                 block_append(
                     newline_node(arg.succ_block),
                     newline_node(
                         NEW_CALL(
-                          gettable(rb_intern("$~")),
+                          gettable(idBACKREF),
                           rb_intern("begin"),
                           NEW_LIST(NEW_LIT(INT2FIX(0)))))),
                 block_append(
@@ -10712,7 +10712,7 @@ rb_parser_append_print(VALUE vparser, NODE *node)
 
     node = block_append(node,
 			NEW_FCALL(rb_intern("print"),
-				  NEW_ARRAY(NEW_GVAR(rb_intern("$_")))));
+				  NEW_ARRAY(NEW_GVAR(idLASTLINE))));
     if (prelude) {
 	prelude->nd_body = node;
 	scope->nd_body = prelude;
@@ -10743,12 +10743,12 @@ rb_parser_while_loop(VALUE vparser, NODE *node, int chop, int split)
     }
     if (split) {
 	node = block_append(NEW_GASGN(rb_intern("$F"),
-				      NEW_CALL(NEW_GVAR(rb_intern("$_")),
+				      NEW_CALL(NEW_GVAR(idLASTLINE),
 					       rb_intern("split"), 0)),
 			    node);
     }
     if (chop) {
-	node = block_append(NEW_CALL(NEW_GVAR(rb_intern("$_")),
+	node = block_append(NEW_CALL(NEW_GVAR(idLASTLINE),
 				     rb_intern("chop!"), 0), node);
     }