# 0.instance\_eval { def m() :m end }; p 1.m

**URL:** <https://www.ruby-forum.com/t/0-instance-eval-def-m-m-end-p-1-m/136537>\
**Category:** Development\
**Created:** [May 3, 2008, 8:00am UTC](https://www.ruby-forum.com/t/0-instance-eval-def-m-m-end-p-1-m/136537 "2008-05-03T08:00:47Z")\
**Posts on this page:** 3\
**Page:** 1

<div class="post-metadata">

**Author:** ![Tanaka\_A](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/t/c67d28/32.png) [@Tanaka\_A](https://www.ruby-forum.com/u/Tanaka_A)\
**Post date:** [May 3, 2008, 8:00am UTC](https://www.ruby-forum.com/t/0-instance-eval-def-m-m-end-p-1-m/136537/1 "2008-05-03T08:00:47Z")

</div>

e$B0J2\<$N$h$&$Ke(B 0.m e$B$rDj5A$G$-!"$=$l$re(B 1.m  
e$B$H$7$F8F$S=P$;$k$N$Oe(B  
e$BJQ$@$H;W$$$^$9!#e(B

% ./ruby -ve ‘0.instance\_eval { def m() :m end }; p 1.m’  
ruby 1.9.0 (2008-05-02 revision 16276) [i686-linux]  
:m

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<div class="post-metadata">

**Author:** ![Tanaka\_A](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/t/c67d28/32.png) [@Tanaka\_A](https://www.ruby-forum.com/u/Tanaka_A)\
**Post date:** [May 18, 2008, 8:34am UTC](https://www.ruby-forum.com/t/0-instance-eval-def-m-m-end-p-1-m/136537/2 "2008-05-18T08:34:03Z")

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e$B!!$5$5$@$G$9!%e(B

Tanaka A. wrote:

> e$B0J2\<$N$h$&$Ke(B 0.m e$B$rDj5A$G$-!"$=$l$re(B 1.m e$B$H$7$F8F$S=P$;$k$N$Oe(B  
> e$BJQ$@$H;W$$$^$9!#e(B
> 
> % ./ruby -ve ‘0.instance\_eval { def m() :m end }; p 1.m’  
> ruby 1.9.0 (2008-05-02 revision 16276) [i686-linux]  
> :m

e$B!!$I$&$7$?$b$s$G$7$g$&!%e(B

1. 1.8 e$B$HF1MM$Ke(B no class/module to add method (TypeError)
2. e$B$3$N$^$^e(B

e$B!!$d$O$j!$e(B1 e$B$+$J$!!%e(B

---

<div class="post-metadata">

**Author:** ![Tanaka\_A](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/t/c67d28/32.png) [@Tanaka\_A](https://www.ruby-forum.com/u/Tanaka_A)\
**Post date:** [May 18, 2008, 2:47pm UTC](https://www.ruby-forum.com/t/0-instance-eval-def-m-m-end-p-1-m/136537/3 "2008-05-18T14:47:17Z")

</div>

e$B$^$D$b$He(B e$B$f$-$R$m$G$9e(B

In message “Re: [ruby-dev:34737] Re: 0.instance\_eval { def m() :m end };  
p 1.m”  
on Sun, 18 May 2008 15:33:27 +0900, SASADA Koichi [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid)  
writes:

|e$B!!$I$&$7$?$b$s$G$7$g$&!%e(B  
|  
|1) 1.8 e$B$HF1MM$Ke(B no class/module to add method (TypeError)  
|2) e$B$3$N$^$^e(B  
|  
|e$B!!$d$O$j!$e(B1 e$B$+$J$!!%e(B

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