# Irb cannot parse /\\^/

**URL:** <https://www.ruby-forum.com/t/irb-cannot-parse/74133>\
**Category:** Development\
**Created:** [February 27, 2006, 1:22pm UTC](https://www.ruby-forum.com/t/irb-cannot-parse/74133 "2006-02-27T13:22:19Z")\
**Posts on this page:** 8\
**Page:** 1

<div class="post-metadata">

**Author:** ![H.Yamamoto](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/h/eb9ed0/32.png) [@H.Yamamoto](https://www.ruby-forum.com/u/H.Yamamoto)\
**Post date:** [February 27, 2006, 1:22pm UTC](https://www.ruby-forum.com/t/irb-cannot-parse/74133/1 "2006-02-27T13:22:19Z")

</div>

e$B;3K$G$9!#e(B

[http://rubyforge.org/tracker/index.php?func=detail&aid=3302&group\_id=426&atid=1698](http://rubyforge.org/tracker/index.php?func=detail&aid=3302&group_id=426&atid=1698)

e$B$NLdBj$J$N$G$9$,!"2\<$N%Q%C%A$G\<#$k$h$&$G$9!#$3$l$G4V0c$$$J$$$G$7$g$&$+!)e(B

# [ruby-talk:181631] e$B$NJ}$Ke(B rdoc

e$B$NF1MM$NLdBj$,Js9p$5$l$F$?$N$G$9$,!"%Q%C%A$be(B

# e$BA4$/F1$8$K$J$j$^$7$?!#%3!\<%I$N=P=j$,F1$8!)e(B

# Index: ruby-lex.rb

RCS file: /src/ruby/lib/irb/ruby-lex.rb,v  
retrieving revision 1.28  
diff -u -w -b -p -r1.28 ruby-lex.rb  
— ruby-lex.rb 30 Jun 2005 10:07:29 -0000 1.28  
+++ ruby-lex.rb 27 Feb 2006 12:10:40 -0000  
@@ -309,7 +309,7 @@ class RubyLex  
“q” =\> “'”,  
“Q” =\> “"”,  
“x” =\> “`”,

- “r” =\> “/”,

- “r” =\> “/”,  
“w” =\> “]”,  
“W” =\> “]”,  
“s” =\> “:”  
@@ -326,14 +326,14 @@ class RubyLex  
“'” =\> TkSTRING,  
“"” =\> TkSTRING,  
“`” =\> TkXSTRING,

- “/” =\> TkREGEXP,

- “/” =\> TkREGEXP,  
“]” =\> TkDSTRING,  
“:” =\> TkSYMBOL  
}  
DLtype2Token = {  
“"” =\> TkDSTRING,  
“`” =\> TkDXSTRING,

- “/” =\> TkDREGEXP,

- “/” =\> TkDREGEXP,  
}

def lex\_init()  
@@ -1040,7 +1040,7 @@ class RubyLex  
break  
elsif @ltype != “'” && @ltype != “]” && @ltype != “:” and ch == “#”  
subtype = true

- elsif ch == ‘\’ #’

- elsif @ltype != “'” && @ltype != “/” and ch == ‘\’ #’  
read\_escape  
end  
if PERCENT\_PAREN.values.include?(@quoted)

---

<div class="post-metadata">

**Author:** ![H.Yamamoto](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/h/eb9ed0/32.png) [@H.Yamamoto](https://www.ruby-forum.com/u/H.Yamamoto)\
**Post date:** [February 27, 2006, 1:40pm UTC](https://www.ruby-forum.com/t/irb-cannot-parse/74133/2 "2006-02-27T13:40:33Z")

</div>

e$B$1$$$8$e!w$$$7$D$+$G$9e(B.

In [ruby-dev:28404] the message: “[ruby-dev:28404] irb cannot parse  
/^/”, on Feb/27 21:19(JST) H.Yamamoto [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) writes:

> e$B;3K$G$9!#e(B

> e$B$NLdBj$J$N$G$9$,!"2\<$N%Q%C%A$G\<#$k$h$&$G$9!#$3$l$G4V0c$$$J$$$G$7$g$&e(B  
> e$B$+!)e(B

e$B$^$@e(B, e$B$A$c$s$H3NG’$7$F$$$^$;$s$,e(B,  
e$BA0H\>$O$=$N$H$\*$j$N5$$,$7$F$$$^$9e(B.  
e$B:G8e$Ne(B:

> def lex\_init()  
> @@ -1040,7 +1040,7 @@ class RubyLex  
> break  
> elsif @ltype != “'” && @ltype != “]” && @ltype != “:” and ch == “#”  
> subtype = true
> 
> - elsif ch == ‘\’ #’
> 
> - elsif @ltype != “'” && @ltype != “/” and ch == ‘\’ #’  
> read\_escape  
> end  
> if PERCENT\_PAREN.values.include?(@quoted)

e$B$NItJ,$G$9$,e(B, e$B860x$OJL$K$"$j$=$&e(B.

Rubye$B$G$Oe(B,

“^C”

e$B$H$+$,0JA0$O5v$5$l$F$$$?$H;W$&$s$G$9$,e(B,  
e$B$$$^$O5v$5$l$F$$$J$$e(B?

\_\_  
----------------------------------------------------\>\> e$B@PDMe(B  
e$B7=\<ye(B \<\<—  
----------------------------------\>\> e-mail: removed\_email\_address@domain.invalid \<\<—

---

<div class="post-metadata">

**Author:** ![H.Yamamoto](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/h/eb9ed0/32.png) [@H.Yamamoto](https://www.ruby-forum.com/u/H.Yamamoto)\
**Post date:** [February 27, 2006, 2:38pm UTC](https://www.ruby-forum.com/t/irb-cannot-parse/74133/3 "2006-02-27T14:38:31Z")

</div>

e$B;3K$G$9!#e(B

> > read\_escape  
> > end  
> > if PERCENT\_PAREN.values.include?(@quoted)
> 
> e$B$NItJ,$G$9$,e(B, e$B860x$OJL$K$"$j$=$&e(B.
> 
> Rubye$B$G$Oe(B,
> 
> “^C”
> 
> e$B$H$+$,0JA0$O5v$5$l$F$$$?$H;W$&$s$G$9$,e(B, e$B$$$^$O5v$5$l$F$$$J$$e(B?

e$B$`!"$=$&$$$&\>l9g$Oe(B @ltype e$B$,e(B “”"  
e$B$K$J$k$s$8$c$J$$$+$H;W$$$^$9!#e(B

# 

e$B$3$N%Q%C%A$O!"@55,I=8=$H%7%s%0%k%/%\*!\<%HJ8;zNs$NCf$G%(%9%1!\<%W=hM}$re(B

# e$BL58z$K$9$k$3$H$r0U?^$7$F$$$^$9!#$H$$$C$F$b!"$3$N%Q%C%A$GK\Ev$Ke(B

# e$B$=$&$G$-$F$$$k$+\<+?.$,$J$$$N$G$9$,!J4@!Ke(B

---

<div class="post-metadata">

**Author:** ![H.Yamamoto](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/h/eb9ed0/32.png) [@H.Yamamoto](https://www.ruby-forum.com/u/H.Yamamoto)\
**Post date:** [February 27, 2006, 3:15pm UTC](https://www.ruby-forum.com/t/irb-cannot-parse/74133/4 "2006-02-27T15:15:14Z")

</div>

e$B;3K$G$9!#e(B

> e$B$$$(e(B, irb(rubye$B$be(B) e$BJ8;zNs$b@55,I=8=$bF1$8$h$&$K=hM}$5$l$F$$$^$9e(B. e$B%(%9%1!\<e(B  
> e$B%W;EJ}$bF1$8$K$J$C$F$$$^$9e(B. e$B\>/$J$/$H$be(Birbe$B$K4X$7$F$Oe(B, irbe$B$N:n\<T$,8@$&$Ne(B  
> e$B$@$+$i4V0c$$$J$$$G$9e(B(^^;

e$B$9$\_$^$;$s!"4\*0c$$$G$7$?!J4@!Ke(B

irb(main):020:0\> /\t/ =~ “\t”  
=\> 0

> e$B$^$9e(B.
> 
> # e$B$?$V$se(B, e$B$3$N%P%0$Oe(Brubye$B$K$bEv;~$O$"$C$?$N$G$O$J$$$+$He(B…
> 
> e$B$=$l$Oe(B, e$B$H$b$+$/$H$7$Fe(B, ^C e$B$N$h$&$J%(%9%1!\<%W$Oe(Brubye$B$G5v$5$l$J$/$J$C$Fe(B  
> e$B$$$k$N$Ge(B, irbe$B$bF1MM$K$9$l$Pe(B, e$B$3$N%P%0$O$J$/$J$j$^$9e(B.

e$B$\*G$$;$7$^$9!#e(B

---

<div class="post-metadata">

**Author:** ![H.Yamamoto](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/h/eb9ed0/32.png) [@H.Yamamoto](https://www.ruby-forum.com/u/H.Yamamoto)\
**Post date:** [February 27, 2006, 2:56pm UTC](https://www.ruby-forum.com/t/irb-cannot-parse/74133/5 "2006-02-27T14:56:46Z")

</div>

e$B$1$$$8$e!w$$$7$D$+$G$9e(B.

In [ruby-dev:28406] the message: “[ruby-dev:28406] Re: irb cannot  
parse /^/”, on Feb/27 22:37(JST) H.Yamamoto [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid)  
writes:

> e$B;3K$G$9!#e(B

> > Rubye$B$G$Oe(B,  
> > “^C”  
> > e$B$H$+$,0JA0$O5v$5$l$F$$$?$H;W$&$s$G$9$,e(B, e$B$$$^$O5v$5$l$F$$$J$$e(B?
> 
> e$B$`!"$=$&$$$&\>l9g$Oe(B @ltype e$B$,e(B “"” e$B$K$J$k$s$8$c$J$$$+$H;W$$$^$9!#e(B

e$B$$$(e(B, irb(rubye$B$be(B)  
e$BJ8;zNs$b@55,I=8=$bF1$8$h$&$K=hM}$5$l$F$$$^$9e(B. e$B%(%9%1!\<e(B  
e$B%W;EJ}$bF1$8$K$J$C$F$$$^$9e(B. e$B\>/$J$/$H$be(Birbe$B$K4X$7$F$Oe(B,  
irbe$B$N:n\<T$,8@$&$Ne(B  
e$B$@$+$i4V0c$$$J$$$G$9e(B(^^;

e$B$b$&e(B, e$B2a5n$N$3$H$J$N$G$9$,e(B, e$B0JA0$Ne(Brubye$B$G$Oe(B,

^C

e$B$G%3%s%H%m!\<%kJ8;z$N%(%9%1!\<%W$,$G$-$k$h$&$K$J$C$F$$$?e(B,  
e$B$=$l$r$^$M$Fe(B  
irbe$B$b:n$j$^$7$?e(B. e$B$=$N$&$Ae(B, rubye$B$NJ}$G$Oe(B,

^C

e$B$,$r5v$5$l$J$/$J$C$?$s$@$1$I$be(B,  
irbe$B$O$=$N$^$^$@$C$?$H$$$&$3$H$@$H;W$$e(B  
e$B$^$9e(B.

# e$B$?$V$se(B,

e$B$3$N%P%0$Oe(Brubye$B$K$bEv;~$O$"$C$?$N$G$O$J$$$+$He(B…

e$B$=$l$Oe(B, e$B$H$b$+$/$H$7$Fe(B, ^C  
e$B$N$h$&$J%(%9%1!\<%W$Oe(Brubye$B$G5v$5$l$J$/$J$C$Fe(B  
e$B$$$k$N$Ge(B, irbe$B$bF1MM$K$9$l$Pe(B, e$B$3$N%P%0$O$J$/$J$j$^$9e(B.

\_\_  
----------------------------------------------------\>\> e$B@PDMe(B  
e$B7=\<ye(B \<\<—  
----------------------------------\>\> e-mail: removed\_email\_address@domain.invalid \<\<—

---

<div class="post-metadata">

**Author:** ![H.Yamamoto](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/h/eb9ed0/32.png) [@H.Yamamoto](https://www.ruby-forum.com/u/H.Yamamoto)\
**Post date:** [February 28, 2006, 4:14pm UTC](https://www.ruby-forum.com/t/irb-cannot-parse/74133/6 "2006-02-28T16:14:33Z")

</div>

e$B;3K$G$9!#e(B

> > e$B$9$\_$^$;$s!"4\*0c$$$G$7$?!J4@!Ke(B  
> > irb(main):020:0\> /\t/ =~ “\t”  
> > =\> 0
> 
> e$B$3$l$G$Oe(B, e$B3NG’$K$O$J$C$F$$$J$$$h$&$J5$$,$7$^$9$,e(B…

e$B$9$\_$^$;$s!J4@!Ke(B

> e$B$=$l$O$H$b$+$/e(B, e$BJs9p$"$j$,$H$&$4$6$$$^$7$?e(B.
> 
> > > e$B$=$l$Oe(B, e$B$H$b$+$/$H$7$Fe(B, ^C e$B$N$h$&$J%(%9%1!\<%W$Oe(Brubye$B$G5v$5$l$J$/$J$C$Fe(B  
> > > e$B$$$k$N$Ge(B, irbe$B$bF1MM$K$9$l$Pe(B, e$B$3$N%P%0$O$J$/$J$j$^$9e(B.
> > 
> > e$B$\*G$$;$7$^$9!#e(B
> 
> e$B$H$j$"$($:e(B, CVS/HEAD e$B$NJ}$rD\>$7$^$7$?e(B. 1.8e$B7O$O$b$&$A$g$C$H$?$C$F$+$iD\>e(B  
> e$B$7$^$9e(B.

e$BF1$8%Q%C%A$rEv$F$k$3$H$Ge(B ruby-talk e$B$GJs9p$5$l$?e(B rdoc  
e$B$N%P%0$be(B  
e$BD\>$j$^$7$?!#$3$A$i$O;d$N$[$&$G%3%\_%C%H$7$F$\*$-$^$9!#e(B

---

<div class="post-metadata">

**Author:** ![H.Yamamoto](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/h/eb9ed0/32.png) [@H.Yamamoto](https://www.ruby-forum.com/u/H.Yamamoto)\
**Post date:** [February 28, 2006, 4:23pm UTC](https://www.ruby-forum.com/t/irb-cannot-parse/74133/7 "2006-02-28T16:23:49Z")

</div>

e$B$1$$$8$e!w$$$7$D$+$G$9e(B.

In [ruby-dev:28411] the message: “[ruby-dev:28411] Re: irb cannot  
parse /^/”, on Mar/01 00:14(JST) H.Yamamoto [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid)  
writes:

> e$B;3K$G$9!#e(B

> e$BF1$8%Q%C%A$rEv$F$k$3$H$Ge(B ruby-talk e$B$GJs9p$5$l$?e(B rdoc e$B$N%P%0$be(B  
> e$BD\>$j$^$7$?!#$3$A$i$O;d$N$[$&$G%3%\_%C%H$7$F$\*$-$^$9!#e(B

e$BN;2r$G$9e(B.  
e$B$C$Fe(B, e$B;d$,8@$&$3$H$G$O$J$$$Je(B.

\_\_  
----------------------------------------------------\>\> e$B@PDMe(B  
e$B7=\<ye(B \<\<—  
----------------------------------\>\> e-mail: removed\_email\_address@domain.invalid \<\<—

---

<div class="post-metadata">

**Author:** ![H.Yamamoto](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/h/eb9ed0/32.png) [@H.Yamamoto](https://www.ruby-forum.com/u/H.Yamamoto)\
**Post date:** [February 28, 2006, 2:51pm UTC](https://www.ruby-forum.com/t/irb-cannot-parse/74133/8 "2006-02-28T14:51:33Z")

</div>

e$B$1$$$8$e!w$$$7$D$+$G$9e(B.

In [ruby-dev:28408] the message: “[ruby-dev:28408] Re: irb cannot  
parse /^/”, on Feb/27 23:15(JST) H.Yamamoto [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid)  
writes:

> e$B;3K$G$9!#e(B
> 
> e$B$9$\_$^$;$s!"4\*0c$$$G$7$?!J4@!Ke(B  
> irb(main):020:0\> /\t/ =~ “\t”  
> =\> 0

e$B$3$l$G$Oe(B, e$B3NG’$K$O$J$C$F$$$J$$$h$&$J5$$,$7$^$9$,e(B…

e$B$=$l$O$H$b$+$/e(B, e$BJs9p$"$j$,$H$&$4$6$$$^$7$?e(B.

> > e$B$=$l$Oe(B, e$B$H$b$+$/$H$7$Fe(B, ^C e$B$N$h$&$J%(%9%1!\<%W$Oe(Brubye$B$G5v$5$l$J$/$J$C$Fe(B  
> > e$B$$$k$N$Ge(B, irbe$B$bF1MM$K$9$l$Pe(B, e$B$3$N%P%0$O$J$/$J$j$^$9e(B.
> 
> e$B$\*G$$;$7$^$9!#e(B

e$B$H$j$"$($:e(B, CVS/HEAD e$B$NJ}$rD\>$7$^$7$?e(B.  
1.8e$B7O$O$b$&$A$g$C$H$?$C$F$+$iD\>e(B  
e$B$7$^$9e(B.

# Index: lib/irb/ruby-lex.rb

RCS file: /src/ruby/lib/irb/ruby-lex.rb,v  
retrieving revision 1.28  
diff -u -r1.28 ruby-lex.rb  
— lib/irb/ruby-lex.rb 30 Jun 2005 10:07:29 -0000 1.28  
+++ lib/irb/ruby-lex.rb 28 Feb 2006 13:39:47 -0000  
@@ -309,7 +309,7 @@  
“q” =\> “'”,  
“Q” =\> “"”,  
“x” =\> “`”,

- “r” =\> “/”,

- “r” =\> “/”,  
“w” =\> “]”,  
“W” =\> “]”,  
“s” =\> “:”  
@@ -326,14 +326,14 @@  
“'” =\> TkSTRING,  
“"” =\> TkSTRING,  
“`” =\> TkXSTRING,

- “/” =\> TkREGEXP,

- “/” =\> TkREGEXP,  
“]” =\> TkDSTRING,  
“:” =\> TkSYMBOL  
}  
DLtype2Token = {  
“"” =\> TkDSTRING,  
“`” =\> TkDXSTRING,

- “/” =\> TkDREGEXP,

- “/” =\> TkDREGEXP,  
}

def lex\_init()  
@@ -1087,7 +1087,7 @@  
def read\_escape  
case ch = getc  
when “\n”, “\r”, “\f”

- when “\”, “n”, “t”, “r”, “f”, “v”, “a”, “e”, “b” #"

- when “\”, “n”, “t”, “r”, “f”, “v”, “a”, “e”, “b”, “s” #"  
when /[0-7]/  
ungetc ch  
3.times do  
@@ -1122,7 +1122,7 @@  
end  
end

- when “C”, “c”, “^”

- when “C”, “c” #, “^”  
if ch == “C” and (ch = getc) != “-”  
ungetc  
elsif (ch = getc) == “\” #"

\_\_  
----------------------------------------------------\>\> e$B@PDMe(B  
e$B7=\<ye(B \<\<—  
----------------------------------\>\> e-mail: removed\_email\_address@domain.invalid \<\<—