From: nobu.nakada@...
Date: 2001-12-14T00:53:10+09:00
Subject: [ruby-dev:15434] [EXP] private instance variable

なかだです。

ふと思い立って以前話にあがっていたprivate instance variable(で
いいんだっけ)を作ってみました。別クラスで定義したものにアクセス
する手段がないとか、module_evalの中で定義したメソッドでは外側の
名前になってしまうとか、かなり手抜きですが参考までに。


Index: parse.y
===================================================================
RCS file: /cvs/ruby/src/ruby/parse.y,v
retrieving revision 1.136
diff -u -2 -p -r1.136 parse.y
--- parse.y	2001/12/11 03:48:08	1.136
+++ parse.y	2001/12/13 15:24:29
@@ -96,4 +96,5 @@ static stack_type cmdarg_stack = 0;
 #define CMDARG_P() (cmdarg_stack&1)
 
+static VALUE nest_scope;
 static int class_nest = 0;
 static int in_single = 0;
@@ -1413,4 +1414,5 @@ primary		: literal
 			    yyerror("class definition in method body");
 			class_nest++;
+			rb_ary_push(nest_scope, ID2SYM($2));
 			local_push();
 		        $<num>$ = ruby_sourceline;
@@ -1422,4 +1424,5 @@ primary		: literal
 		        nd_set_line($$, $<num>4);
 		        local_pop();
+			rb_ary_pop(nest_scope);
 			class_nest--;
 		    }
@@ -1451,4 +1454,5 @@ primary		: literal
 			    yyerror("module definition in method body");
 			class_nest++;
+			rb_ary_push(nest_scope, ID2SYM($2));
 			local_push();
 		        $<num>$ = ruby_sourceline;
@@ -1459,4 +1463,5 @@ primary		: literal
 		        $$ = NEW_MODULE($2, $4);
 		        nd_set_line($$, $<num>3);
+			rb_ary_pop(nest_scope);
 		        local_pop();
 			class_nest--;
@@ -2146,5 +2151,13 @@ yycompile(f, line)
     ruby_sourcefile = f;
     ruby_in_compile = 1;
+    if (!nest_scope) {
+	nest_scope = rb_ary_new();
+	rb_global_variable(&nest_scope);
+    }
+    else {
+	rb_ary_clear(nest_scope);
+    }
     n = yyparse();
+    rb_ary_clear(nest_scope);
     ruby_debug_lines = 0;
     compile_for_eval = 0;
@@ -3804,6 +3817,21 @@ yylex()
 	    if (tok()[1] == '@')
 		result = tCVAR;
-	    else
+	    else {
+		if (tok()[1] == '_' && tok()[2]) {
+		    VALUE scope = 0;
+		    if (in_def && RARRAY(nest_scope)->len) {
+			scope = rb_ary_join(nest_scope, rb_str_new2("::"));
+		    }
+		    else if (compile_for_eval && RNODE(scope = ruby_frame->cbase)->nd_next) {
+			scope = rb_class_path(RNODE(scope)->nd_clss);
+		    }
+		    if (scope) {
+			char *s = RSTRING(scope)->ptr;
+			tokadd('@');
+			while (*s) tokadd(*s++);
+		    }
+		}
 		result = tIVAR;
+	    }
 	    break;
 
@@ -5152,4 +5180,14 @@ rb_intern(name)
 	else {
 	    id |= ID_INSTANCE;
+	    if (name[1] == '_' && name[2]) {
+		while (*m && *m != '@') {
+		    if (!is_identchar(*m)) {
+			id = ID_JUNK;
+			break;
+		    }
+		    m++;
+		}
+		goto id_new;
+	    }
 	}
 	m++;
@@ -5195,4 +5233,5 @@ rb_intern(name)
     }
     if (*m) id = ID_JUNK;
+  id_new:
     id |= ++last_id << ID_SCOPE_SHIFT;
   id_regist:


-- 
--- 僕の前にBugはない。
--- 僕の後ろにBugはできる。
    中田 伸悦