[ruby-dev:31448] Ruby's (new) Bizarre Operator(s)

なかだです。

http://www.rubyist.net/~matz/20070806.html#p01

?.はいろいろとかぶるので、.?と.&にしてみました。

# でもsafe navigationって用語がいまいちわかりにくいかも。


Index: compile.c
===================================================================
--- compile.c	(revision 13073)
+++ compile.c	(working copy)
@@ -3496,4 +3496,5 @@ iseq_compile_each(rb_iseq_t *iseq, LINK_
 	break;
       }
+      case NODE_SAFENAV:
       case NODE_CALL:
       case NODE_FCALL:
@@ -3509,4 +3510,5 @@ iseq_compile_each(rb_iseq_t *iseq, LINK_
 	VALUE argc;
 	unsigned long flag = 0;
+	LABEL *end_label = 0;
 	VALUE parent_block = iseq->compile_data->current_block;
 	iseq->compile_data->current_block = Qfalse;
@@ -3566,5 +3568,5 @@ iseq_compile_each(rb_iseq_t *iseq, LINK_
 #endif
 	/* reciever */
-	if (type == NODE_CALL) {
+	if (type == NODE_CALL || type == NODE_SAFENAV) {
 	    COMPILE(recv, "recv", node->nd_recv);
 	}
@@ -3582,4 +3584,9 @@ iseq_compile_each(rb_iseq_t *iseq, LINK_
 
 	ADD_SEQ(ret, recv);
+	if (type == NODE_SAFENAV) {
+	    end_label = NEW_LABEL(nd_line(node));
+	    ADD_INSN(ret, nd_line(node), dup);
+	    ADD_INSNL(ret, nd_line(node), branchunless, end_label);
+	}
 	ADD_SEQ(ret, args);
 
@@ -3598,4 +3605,15 @@ iseq_compile_each(rb_iseq_t *iseq, LINK_
 		   argc, parent_block, LONG2FIX(flag));
 
+	if (end_label) {
+	    ADD_LABEL(ret, end_label);
+	}
+	if (poped) {
+	    ADD_INSN(ret, nd_line(node), pop);
+	}
+	break;
+      }
+      case NODE_METHOBJ:{
+	COMPILE(ret, "recv", node->nd_recv);
+	ADD_INSN1(ret, nd_line(node), methobj, ID2SYM(node->nd_mid));
 	if (poped) {
 	    ADD_INSN(ret, nd_line(node), pop);
Index: insns.def
===================================================================
--- insns.def	(revision 13073)
+++ insns.def	(working copy)
@@ -1199,4 +1199,18 @@ finish
 }
 
+/**
+  @c method/iterator
+  @e return Method object
+  @j Method オブジェクトを作る
+ */
+DEFINE_INSN
+methobj
+(VALUE mid)
+(VALUE recv)
+(VALUE val)
+{
+    val = rb_obj_method(recv, mid);
+}
+
 /**********************************************************/
 /* deal with control flow 3: exception                    */
Index: parse.y
===================================================================
--- parse.y	(revision 13073)
+++ parse.y	(working copy)
@@ -373,4 +373,6 @@ static NODE *new_yield_gen(struct parser
 static NODE *new_not_gen(struct parser_params*,NODE*);
 #define new_not(node) new_not_gen(parser, node)
+static NODE *new_safenav_gen(struct parser_params*,NODE*,ID,NODE*);
+#define new_safenav(r, m, a) new_safenav_gen(parser, r, m, a)
 
 static NODE *gettable_gen(struct parser_params*,ID);
@@ -682,4 +684,6 @@ static void ripper_compile_error(struct 
 %token tAMPER		/* & */
 %token tLAMBDA		/* -> */
+%token tSAFENAV		/* .? */
+%token tMETHOBJ		/* .& */
 %token tSYMBEG tSTRING_BEG tXSTRING_BEG tREGEXP_BEG tWORDS_BEG tQWORDS_BEG
 %token tSTRING_DBEG tSTRING_DVAR tSTRING_END tLAMBEG
@@ -702,4 +706,5 @@ static void ripper_compile_error(struct 
 %left  tOROP
 %left  tANDOP
+%left  tSAFENAV
 %nonassoc  tCMP tEQ tEQQ tNEQ tMATCH tNMATCH
 %left  '>' tGEQ '<' tLEQ
@@ -708,5 +713,5 @@ static void ripper_compile_error(struct 
 %left  tLSHFT tRSHFT
 %left  '+' '-'
-%left  '*' '/' '%'
+%left  '*' '/' '%' tMETHOBJ
 %right tUMINUS_NUM tUMINUS
 %right tPOW
@@ -1305,4 +1310,24 @@ command		: operation command_args       
 		    %*/
 		   }
+		| primary_value tSAFENAV operation2 command_args	%prec tLOWEST
+		    {
+		    /*%%%*/
+			$$ = new_safenav($1, $3, $4);
+			fixpos($$, $1);
+		    /*%
+			$$ = dispatch4(command_call, $1, ripper_intern("::"), $3, $4);
+		    %*/
+		    }
+		| primary_value tSAFENAV operation2 command_args cmd_brace_block
+		    {
+		    /*%%%*/
+			$$ = new_safenav($1, $3, $4);
+			block_dup_check($4, $5);
+			fixpos($$, $1);
+		    /*%
+			$$ = dispatch4(command_call, $1, ripper_intern("::"), $3, $4);
+			$$ = dispatch2(iter_block, $$, $5);
+		    %*/
+		   }
 		| keyword_super command_args
 		    {
@@ -1996,4 +2021,12 @@ arg		: lhs '=' arg
 		    %*/
 		    }
+		| arg tMETHOBJ operation2
+		    {
+		    /*%%%*/
+			$$ = NEW_METHOBJ($1, $3);
+		    /*%
+			$$ = dispatch3(binary, $1, ID2SYM('%'), $3);
+		    %*/
+		    }
 		| tUMINUS_NUM tINTEGER tPOW arg
 		    {
@@ -3403,4 +3436,14 @@ method_call	: operation paren_args
 		    %*/
 		    }
+		| primary_value tSAFENAV operation2 opt_paren_args
+		    {
+		    /*%%%*/
+			$$ = new_safenav($1, $3, $4);
+			fixpos($$, $1);
+		    /*%
+			$$ = dispatch3(call, $1, ripper_id2sym('.'), $3);
+			$$ = method_optarg($$, $4);
+		    %*/
+		    }
 		| keyword_super paren_args
 		    {
@@ -3431,4 +3474,16 @@ method_call	: operation paren_args
 		    %*/
 		    }
+		| primary_value tSAFENAV '[' aref_args ']'
+		    {
+		    /*%%%*/
+			if ($1 && nd_type($1) == NODE_SELF)
+			    $$ = logop(NODE_AND, $1, NEW_FCALL(tAREF, $4));
+			else
+			    $$ = NEW_SAFENAV($1, tAREF, $4);
+			fixpos($$, $1);
+		    /*%
+			$$ = dispatch2(aref, $1, escape_Qundef($4));
+		    %*/
+		    }
 		;
 
@@ -6115,5 +6170,6 @@ parser_yylex(struct parser_params *parse
       case '.':
 	lex_state = EXPR_BEG;
-	if ((c = nextc()) == '.') {
+	switch (c = nextc()) {
+	  case '.':
 	    if ((c = nextc()) == '.') {
 		return tDOT3;
@@ -6121,4 +6177,11 @@ parser_yylex(struct parser_params *parse
 	    pushback(c);
 	    return tDOT2;
+	  case '&':
+	    if (peek('(')) break;
+	    lex_state = EXPR_DOT;
+	    return tMETHOBJ;
+	  case '?':
+	    lex_state = EXPR_DOT;
+	    return tSAFENAV;
 	}
 	pushback(c);
@@ -7963,4 +8026,14 @@ new_args_gen(struct parser_params *parse
 }
 
+static NODE*
+new_safenav_gen(struct parser_params *parser, NODE *r, ID m, NODE *a)
+{
+    if (a && nd_type(a) == NODE_BLOCK_PASS) {
+	a->nd_iter = NEW_SAFENAV(r,m,a->nd_head);
+	return a;
+    }
+    return NEW_SAFENAV(r,m,a);
+}
+
 static void
 local_push_gen(struct parser_params *parser, int inherit_dvars)
Index: include/ruby/node.h
===================================================================
--- include/ruby/node.h	(revision 13073)
+++ include/ruby/node.h	(working copy)
@@ -240,4 +240,8 @@ enum node_type {
     NODE_OPTBLOCK,
 #define NODE_OPTBLOCK    NODE_OPTBLOCK
+    NODE_SAFENAV,
+#define NODE_SAFENAV     NODE_SAFENAV
+    NODE_METHOBJ,
+#define NODE_METHOBJ     NODE_METHOBJ
     NODE_LAST
 #define NODE_LAST        NODE_LAST
@@ -436,4 +440,5 @@ enum ruby_node_flags {
 #define NEW_FCALL(m,a) NEW_NODE(NODE_FCALL,0,m,a)
 #define NEW_VCALL(m) NEW_NODE(NODE_VCALL,0,m,0)
+#define NEW_SAFENAV(r,m,a) NEW_NODE(NODE_SAFENAV,r,m,a)
 #define NEW_SUPER(a) NEW_NODE(NODE_SUPER,0,0,a)
 #define NEW_ZSUPER() NEW_NODE(NODE_ZSUPER,0,0,0)
@@ -471,4 +476,5 @@ enum ruby_node_flags {
 #define NEW_PRELUDE(p,b) NEW_NODE(NODE_PRELUDE,p,b,0)
 #define NEW_OPTBLOCK(a) NEW_NODE(NODE_OPTBLOCK,a,0,0)
+#define NEW_METHOBJ(r,m) NEW_NODE(NODE_METHOBJ,r,m,0)
 
 #define NOEX_PUBLIC    0x00


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