[Feature #747] /\A/u ignores BOM

Ruby Development
1

Feature #747: /\A/u ignores BOM
http://redmine.ruby-lang.org/issues/show/747

e$B5/I<<Te(B: Shyouhei U.
e$B%9%F!<%?%9e(B: Open, e$BM%@hEYe(B: Normal
e$BC4Ev<Te(B: Yui NARUSE, e$B%+%F%4%je(B: M17N, Target version: 1.9.x

/\A/ue$B$,e(BBOMe$B$K%R%C%H$7$J$$$N$,4r$7$/$J$$$G$9!#IaDL!“e(BBOMe$B$O$”$k$H$9$l$PJ8;zNs$N@hF,$KIU$$$F$$$k$3$H$,B?$$$N$G!"e(B/\A/ue$B$,e(BBOMe$B$K%R%C%H$9$k$N$,<+A3$@$H;W$$$^$9!#e(B

e$B$“$k$$$Oe(B/\Z/e$B$He(B/\z/e$B$N$h$&$Ke(BBOMe$B$K%R%C%H$9$ke(B/\a/e$B$H$7$J$$e(B/\A/e$B$H$+$”$C$F$b$$$$$+$b$7$l$^$;$s$,!"$$$:$l$K$;$he(BBOMe$B$rE,@Z$K@hF,$H$_$J$7$F$/$l$k%a%?%-%c%i%/%?$r4uK>$7$^$9!#$G$J$$$HKh2se(B
/\A(\xEF\xBB\xBF)?/ue$B$H$+=q$+$J$$$H$$$1$J$/$J$C$FHs>o$KLLE]$G$9!#e(B

% ~/target/branches/ruby_1_9_1/bin/ruby -Ku -ve ‘p /\Afoo/u =~
“\xEF\xBB\xBFfoo”’
ruby 1.9.1 (2008-11-12 revision 20221) [x86_64-linux]
-e:1: warning: ambiguous first argument; put parentheses or even spaces
nil

2

On Wed, 12 Nov 2008 17:49:47 +0900
In article [email protected]
[[ruby-dev:37075] [Feature #747] /\A/u ignores BOM]
Shyouhei U. [email protected] wrote:

/\A/ue$B$,e(BBOMe$B$K%R%C%H$7$J$$$N$,4r$7$/$J$$$G$9!#IaDL!“e(BBOMe$B$O$”$k$H$9$l$PJ8;zNs$N@hF,$KIU$$$F$$$k$3$H$,B?$$$N$G!"e(B/\A/ue$B$,e(BBOMe$B$K%R%C%H$9$k$N$,<+A3$@$H;W$$$^$9!#e(B

http://www.ietf.org/rfc/rfc3629.txt
RFC 3629 e$B$rFI$`$H!“FbIt=hM}$K$Oe(B U+FEFF
e$B$rFCJL07$$$7$J$$$3$H$r?d>)$7$F$$e(B
e$B$k$h$&$K;W$$$^$9$,!”$I$&$J$s$G$7$g$&!#e(B

3

e$BKNIt$G$9!#e(B

Tietew e$B$5$s$O=q$-$^$7$?e(B:

RFC 3629 e$B$rFI$`$H!“FbIt=hM}$K$Oe(B U+FEFF e$B$rFCJL07$$$7$J$$$3$H$r?d>)$7$F$$e(B
e$B$k$h$&$K;W$$$^$9$,!”$I$&$J$s$G$7$g$&!#e(B

e$BF1$8e(BRFCe$B$K!"e(B

It is therefore RECOMMENDED to avoid stripping an initial U+FEFF
interpreted as a signature without a good reason, to ignore it instead
of stripping it when appropriate (such as for display) and to strip it
only when really necessary.

e$B$H$"$j$^$9!#@lLg2H$G$O$J$$$N$G30$7$F$k$+$b$7$l$^$;$s$,!"$3$Ne(B(such
as for
display)e$B$N$H$3$m$K@55,I=8=%^%C%A$b4^$^$l$k$s$8$c$J$$$G$7$g$&$+!#e(B

4

e$BLZB<$G$9!#e(B

Shyouhei U. e$B$5$s$O=q$-$^$7$?e(B:

% ~/target/branches/ruby_1_9_1/bin/ruby -Ku -ve ‘p /\Afoo/u =~ “\xEF\xBB\xBFfoo”’
ruby 1.9.1 (2008-11-12 revision 20221) [x86_64-linux]
-e:1: warning: ambiguous first argument; put parentheses or even spaces
nil

BOMe$B$r$I$&$K$+$7$?$$$H$$$&$N$OF146$G$9$,!“e(B\Ae$B$O!V%”%s%+!<!W$H$J$k%a%?J8;ze(B
e$B$J$N$G!“e(B
e$B%”%s%+!<$G$O$J$/$J$ke(B(e$B!VI}$r$b$D!We(B)e$B$h$&$JF0:n$ONI$/$J$$$h$&$J5$$,$7$^$9!#e(B
e$BJ8;zNs@hF,$K$"$ke(B\xef\xbb\bfe$B$ND>8e!"$H$$$&$N$b9M$($i$l$J$/$b$J$$$G$9$,!"e(B
e$B$3$l$O$3$l$G$&$l$7$/$J$$$G$9$M$(!#e(B

5

e$B$3$s$K$A$O!"$J$+$`$ie(B(e$B$&e(B)e$B$G$9!#e(B

In message “[ruby-dev:37077] Re: [Feature #747] /\A/u ignores BOM”
on Nov.12,2008 18:40:30, [email protected] wrote:

/\A/ue$B$,e(BBOMe$B$K%R%C%H$7$J$$$N$,4r$7$/$J$$$G$9!#IaDL!“e(BBOMe$B$O$”$k$H$9$l$PJ8;zNs$N@hF,$KIU$$$F$$$k$3$H$,B?$$$N$G!"e(B/\A/ue$B$,e(BBOMe$B$K%R%C%H$9$k$N$,<+A3$@$H;W$$$^$9!#e(B

http://www.ietf.org/rfc/rfc3629.txt
RFC 3629 e$B$rFI$`$H!“FbIt=hM}$K$Oe(B U+FEFF e$B$rFCJL07$$$7$J$$$3$H$r?d>)$7$F$$e(B
e$B$k$h$&$K;W$$$^$9$,!”$I$&$J$s$G$7$g$&!#e(B

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e$B$d$O$je(BBOMe$B$rM}2r$9$ke(Bopene$B$,I,MW$J$s$8$c$J$$$G$7$g$&$+!#e(B

e$B$J$0JA0$N5DO@$N:]$N7kO@<+BN$Oe(B[ruby-dev:32981]e$B$K$^$H$a$F$“$je(B
e$B$^$9$,!”$"$N;~$O=q$-9~$;~$Ke(BBOMe$B$r$I$&07$($P$$$$$N$+H=CG$G$-$Je(B
e$B$+$C$?$N$,8+Aw$j$N<g860x$G$7$?!#e(B
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e$B$&$H$$$&0F$rDs0F$7$F$$^$9!#e(B

e$B$J$*e(B1.9.1e$B$KF~$l$k$3$H$OA[Dj$7$F$$$^$;$s!#e(B

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"r"e$B;~$N%(%s%3!<%G%#%s%0L>;XDj$H$7$F!"e(B"utf-7-bom"e$B!"e(B"utf-8-bom"e$B!"e(B
"utf-16le-bom"e$B!"e(B"utf-16be-bom"e$B!"e(B"utf-32le-bom"e$B!“e(B"utf-32be-bom”
e$B$r%5%]!<%H$9$k!#e(B
e$B$3$l$i$,;XDj$5$l$?$H$-!“e(BBOMe$B$,$”$k$+$I$&$+H=CG$G$-$k$^$G%U%!e(B
e$B%$%k@hF,$rFI$!“e(BBOMe$B$,$”$l$P$=$Ne(BBOMe$B$K=>$C$?%(%s%3!<%G%#%s%0e(B
e$B$,;XDj$5$l$?$H$$J$7$F!“FI$s$@e(BBOMe$B$O<N$F$k!#e(B
BOMe$B$,$J$1$l$P4{$KFI$s$@J,$re(Bungetbytee$B$7$?>e$Ge(B”-bom"e$B$J$7$N%(e(B
e$B%s%3!<%G%#%s%0$,;XDj$5$l$?$H$_$J$9!#e(B

e$BB>$O8=>u$rJQ99$7$J$$!#$D$^$jNc$($Pe(B"w:utf-8-bom"e$B$J$I$N;XDj$Oe(B
Unsupported encodinge$B$H$7$FL5;k$5$l$k!#e(B

e$B"(e(BUTF-7e$B$Ke(BBOMe$B$,$“$k$N$+$I$&$+$h$/$o$+$i$J$$$s$G$9$,!”@dBP$K$Je(B
e$B$$$s$@$C$?$i>e5-$+$ie(Butf-7-bome$B$O<h$j=|$-$^$9!#e(B

e$B$=$l$G$O!#e(B

6

At 18:40 08/11/12, Tietew wrote:

RFC 3629 e$B$rFI$`$H!“FbIt=hM}$K$Oe(B U+FEFF e$B$rFCJL07$$$7$J$$$3$H$r?d>)$7$F$$e(B
e$B$k$h$&$K;W$$$^$9$,!”$I$&$J$s$G$7$g$&!#e(B

U+FEFF e$B$Oe(B BOM e$B$NLr3d$@$1$G$O$J$/!“e(BZERO WIDTH NON BREAKING
SPACE e$B$H8@$&Lr3de(B
e$B$b$”$j$^$9$7!"@55,I=8=$G$OB?$/$N>l9g%U%!%$%k$N@hF,$G$O$J$/!"C1$J$k2?$+$Ne(B
e$BJ8;zNs$r%^%C%A$7$^$9$N$G!"e(BBOM
e$B$rFCJL07$$:~$k$N$O9%$^$7$/$J$$$H;W$$$^$9!#e(B

e$B$I$&$7$F$b:#$h$je(B Ruby e$B$Ne(B BOM
e$B$X$NBP1~$r6/2=$7$?$$$H$J$i!"J8;zNsJQ49e(B
(e$B%U%!%$%kF~=PNO8BDje(B) e$B$Ge(B :bom => :remove (e$BF~NO$N>l9ge(B)
e$B$H$+e(B :bom => :add
(e$B=PNO$N>l9ge(B) e$B$H$+$NJ}8~$G9M$($?J}$,$$$$$+$H;W$$$^$9!#e(B

e$B59$7$/$*4j$$$7$^$9!#e(B Martin.

#-#-# Martin J. Du"rst, Assoc. Professor, Aoyama Gakuin University
#-#-# http://www.sw.it.aoyama.ac.jp mailto:[email protected]

7

e$B>.@>90>-$G$9!#e(B

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8

At 19:31 08/11/12, Urabe S. wrote:

e$B$N@hF,$KIU$$$F$$$k$3$H$,B?$$$N$G!"e(B/\A/ue$B$,e(BBOMe$B$K%R%C%H$9$k$N$,<+A3$@$H;W$$$^$9!#e(B
of stripping it when appropriate (such as for display) and to strip it
only when really necessary.

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BOM
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e$B6KC<$K8@$&$He(B /\A\uFEFF/u
e$B$O$I$&$$$&>l9g$K%^%C%A$9$Y$-$G$7$g$&$+!#e(B

e$B59$7$/$*4j$$$7$^$9!#e(B Martin.

e$B$H$“$j$^$9!#@lLg2H$G$O$J$$$N$G30$7$F$k$+$b$7$l$^$;$s$,!”$3$Ne(B(such as for
display)e$B$N$H$3$m$K@55,I=8=%^%C%A$b4^$^$l$k$s$8$c$J$$$G$7$g$&$+!#e(B

#-#-# Martin J. Du"rst, Assoc. Professor, Aoyama Gakuin University
#-#-# http://www.sw.it.aoyama.ac.jp mailto:[email protected]

9

e$B$3$s$K$A$O!"$J$+$`$ie(B(e$B$&e(B)e$B$G$9!#e(B

In message “[ruby-dev:37086] Re: [Feature #747] /\A/u ignores BOM”
on Nov.13,2008 17:32:25, [email protected] wrote:

[ruby-dev:32981]e$B$NJ}$bFI$s$G$_$F!“:#$N>u67$,$h$/$o$+$i$J$+$C$?$N$G<ALd$5e(B
e$B$;$F$/$@$5$$!#8=;~E@$Ge(BRuby-1.9e$B7O$Oe(B2BYTE Unicodee$B$NJ8;zNs$rFI$_9~$s$@>le(B
e$B9g!”$I$N$h$&$JFbItI=8=$H$J$k$N$G$7$g$&$+!#e(B

e$B$9$_$^$;$s!"e(B2BYTE Unicodee$B$C$F$J$s$G$7$g$&e(B?

A:
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10

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11

e$B%A%1%C%He(B #747 e$B$,99?7$5$l$^$7$?!#e(B (by Yukihiro M.)

e$B%9%F!<%?%9e(B Opene$B$+$ie(BRejectede$B$KJQ99e(B

BOMe$BBP1~$,ITMW$H$O8@$$$^$;$s$,!"@55,I=8=$GBP1~$9$k$N$O$h$/$J$$$H;W$$$^$9!#e(B

http://redmine.ruby-lang.org/issues/show/747

12

e$B$3$s$K$A$O!"$J$+$`$ie(B(e$B$&e(B)e$B$G$9!#e(B

In message “[ruby-dev:37088] Re: [Feature #747] /\A/u ignores BOM”
on Nov.13,2008 18:13:39, [email protected] wrote:

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In message “Re: [ruby-dev:37223] [Feature #747] /\A/u ignores BOM”
on Fri, 28 Nov 2008 19:18:13 +0900, Shyouhei U.
[email protected] writes:

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http://redmine.ruby-lang.org/issues/show/747