From: Eric Hodel <drbrain@...7.net>
Date: 2006-12-08T06:44:04+09:00
Subject: Re: NoMethodError in protocol.rb

On Dec 7, 2006, at 02:30 , Paul Lutus wrote:
> Alex Young wrote:
>> Does this look familiar to anyone?
>>
>> NoMethodError: undefined method `+' for nil:NilClass at
>> /usr/local/lib/ruby/1.8/net/protocol.rb:176:in `write0'
>>
>> I'm getting it sporadically during some fairly heavy XMLRPC  
>> traffic.  It
>> doesn't make very much sense to me, because write0 looks like this:
>>
>> def write0(str)
>>    @debug_output << str.dump if @debug_output
>>    len = @io.write(str)
>>    @written_bytes += len  # <= line 176
>>    len
>> end
>>
>> The error must mean that @written_bytes is nil.  It's only called  
>> from
>> within a block passed to writing, which looks like this:
>>
>> def writing
>>    @written_bytes = 0
>>    @debug_output << '<- ' if @debug_output
>>    yield
>
> You aren't showing us the block to which this yield refers. Does  
> that block
> modify @written_bytes?

Irrelevant.  #write0 is the code you are looking for.

>>    @debug_output << "\n" if @debug_output
>>    bytes = @written_bytes
>>    @written_bytes = nil
>>    bytes
>
> Okay, here you are modifying the @written_bytes class variable

There are no class variables here, only instance variables.

> , assigning it nil, and this is likely to be the problem. Can I ask  
> why you are using an instance variable here rather than a method- 
> local one? Can't this need be met by a local variable?

This is from protocol.rb.  See #write0 above for why an instance  
variable in necessary.

-- 
Eric Hodel - drbrain@segment7.net - http://blog.segment7.net

I LIT YOUR GEM ON FIRE!