# Error with open-uri (instance\_eval?)

**URL:** <https://www.ruby-forum.com/t/error-with-open-uri-instance-eval/125329>\
**Category:** Development\
**Created:** [January 8, 2008, 10:20am UTC](https://www.ruby-forum.com/t/error-with-open-uri-instance-eval/125329 "2008-01-08T10:20:16Z")\
**Posts on this page:** 4\
**Page:** 1

<div class="post-metadata">

**Author:** ![U.Nakamura](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/u/b5ac83/32.png) [@U.Nakamura](https://www.ruby-forum.com/u/U.Nakamura)\
**Post date:** [January 8, 2008, 10:20am UTC](https://www.ruby-forum.com/t/error-with-open-uri-instance-eval/125329/1 "2008-01-08T10:20:16Z")

</div>

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% ruby -ropen-uri -ve ‘open(“[http://www.ruby-lang.org/](http://www.ruby-lang.org/)”)’  
ruby 1.9.0 (2008-01-08 revision 0) [i386-netbsdelf]  
/home/usa/ruby/lib/ruby/1.9.0/open-uri.rb:411: warning: instance  
variable @meta not initialized  
/home/usa/ruby/lib/ruby/1.9.0/open-uri.rb:411:in `meta_add_field': undefined method `[]=’ for nil:NilClass (NoMethodError)  
from /home/usa/ruby/lib/ruby/1.9.0/open-uri.rb:326:in `block in open_http' from /home/usa/ruby/lib/ruby/1.9.0/net/http.rb:1297:in `block in  
each\_header’  
from /home/usa/ruby/lib/ruby/1.9.0/net/http.rb:1296:in `each' from /home/usa/ruby/lib/ruby/1.9.0/net/http.rb:1296:in `each\_header’  
from /home/usa/ruby/lib/ruby/1.9.0/open-uri.rb:326:in  
`open_http' from /home/usa/ruby/lib/ruby/1.9.0/open-uri.rb:735:in `buffer\_open’  
from /home/usa/ruby/lib/ruby/1.9.0/open-uri.rb:197:in `block in open_loop' from /home/usa/ruby/lib/ruby/1.9.0/open-uri.rb:195:in `catch’  
from /home/usa/ruby/lib/ruby/1.9.0/open-uri.rb:195:in  
`open_loop' from /home/usa/ruby/lib/ruby/1.9.0/open-uri.rb:141:in `open\_uri’  
from /home/usa/ruby/lib/ruby/1.9.0/open-uri.rb:637:in `open' from /home/usa/ruby/lib/ruby/1.9.0/open-uri.rb:33:in `open’  
from -e:1:in `’

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e$B$KJQ$($k$H@5\>o$KF0:n$9$k$N$G!“e(Binstance\_evale$B$,$^$:$$$N$@$H;W$$e(B  
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---

<div class="post-metadata">

**Author:** ![U.Nakamura](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/u/b5ac83/32.png) [@U.Nakamura](https://www.ruby-forum.com/u/U.Nakamura)\
**Post date:** [January 15, 2008, 8:02am UTC](https://www.ruby-forum.com/t/error-with-open-uri-instance-eval/125329/2 "2008-01-15T08:02:59Z")

</div>

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At Tue, 8 Jan 2008 18:19:29 +0900,  
U.Nakamura wrote:

> open-uri.rbe$B$Ne(B386e$B9TL$+$i$Ne(Binstance\_evale$B$r$d$a$Fe(Binstance\_variable\_set  
> e$B$KJQ$($k$H@5\>o$KF0:n$9$k$N$G!“e(Binstance\_evale$B$,$^$:$$$N$@$H;W$$e(B  
> e$B$^$9$,!”$h$/$o$+$j$^$;$s!#e(B

Tempfilee$B$,e(BDelegateClass(File)e$B$Ge(Binstance\_evale$B$,\<B9T$5$l$k%_%V%8%’%/%H$He(B  
meta\_add\_fielde$B$,\<B9T$5$l$k%_%V%8%’%/%H$,$:$l$F$7$^$&$N$,860x$N$h$&$G$9!#e(B

require “delegate”  
module M  
attr\_reader :m  
end  
obj = DelegateClass(Array).new([])  
obj.instance\_eval { @m = :m }  
obj.extend M  
p obj.m

p obj.class  
p Object.instance\_method(:class).bind(obj).call

---

<div class="post-metadata">

**Author:** ![U.Nakamura](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/u/b5ac83/32.png) [@U.Nakamura](https://www.ruby-forum.com/u/U.Nakamura)\
**Post date:** [January 15, 2008, 9:13am UTC](https://www.ruby-forum.com/t/error-with-open-uri-instance-eval/125329/3 "2008-01-15T09:13:11Z")

</div>

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

In message “[ruby-dev:33116] Re: error with open-uri (instance\_eval?)”  
on Jan.15,2008 16:02:24, [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) wrote:  
| \> open-uri.rbe$B$Ne(B386e$B9TL$+$i$Ne(Binstance\_evale$B$r$d$a$Fe(Binstance\_variable\_set  
| \> e$B$KJQ$($k$H@5\>o$KF0:n$9$k$N$G!“e(Binstance\_evale$B$,$^$:$$$N$@$H;W$$e(B  
| \> e$B$^$9$,!”$h$/$o$+$j$^$;$s!#e(B  
|  
| Tempfilee$B$,e(BDelegateClass(File)e$B$Ge(Binstance\_evale$B$,\<B9T$5$l$k%_%V%8%'%/%H$He(B  
| meta\_add\_fielde$B$,\<B9T$5$l$k%_%V%8%'%/%H$,$:$l$F$7$^$&$N$,860x$N$h$&$G$9!#e(B

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e$B$$$$$s$G$7$g$&$+e(B…

# Index: lib/delegate.rb

— lib/delegate.rb (revision 15059)  
+++ lib/delegate.rb (working copy)  
@@ -267,6 +267,7 @@ def DelegateClass(superclass)  
: **id** , :object\_id, : **send** , :public\_send, :respond\_to?, :send,  
:==, :equal?, :initialize, :method\_missing, : **getobj** ,  
: **setobj** ,  
:clone, :dup, :marshal\_dump, :marshal\_load, :instance\_eval,  
:instance\_exec,

- :extend,  
]  
klass.module\_eval {  
include Delegator::MethodDelegation

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

---

<div class="post-metadata">

**Author:** ![U.Nakamura](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/u/b5ac83/32.png) [@U.Nakamura](https://www.ruby-forum.com/u/U.Nakamura)\
**Post date:** [January 15, 2008, 9:20am UTC](https://www.ruby-forum.com/t/error-with-open-uri-instance-eval/125329/4 "2008-01-15T09:20:14Z")

</div>

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In message “Re: [ruby-dev:33117] Re: error with open-uri  
(instance\_eval?)”  
on Tue, 15 Jan 2008 17:12:31 +0900, “U.Nakamura”  
[removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) writes:

|e$B0J2\<$N%Q%C%A$GLdBj$,2r7h$9$k$3$H$,$o$+$j$^$7$?!#e(B  
|e$B$3$NLdBj$O$?$V$s$3$l$G$$$$$s$G$9$,!"$3$&$$$&\>lEv$?$j$JBP1~$Ge(B  
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a.extend(aModule)

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