From: Brian Adkins <lojicdotcom@...>
Date: 2008-12-13T03:13:04+09:00
Subject: Re: why Hash corrupts 'key' object ?

Mike Gold <mike.gold.4433@gmail.com> writes:

> Brian Adkins wrote:
>> 
>> Why would that cause this effect though? The docs say "a String passed
>> as a key will be duplicated and frozen", but duplicating and freezing
>> a TestStr doesn't nullify dupstr:
>
> The answer lies in the rb_hash_aset() function I quoted.  rb_str_new4() 
> begins like this:
>
>   VALUE
>   rb_str_new4(orig)
>       VALUE orig;
>   {
>       VALUE klass, str;
>
>       if (OBJ_FROZEN(orig)) return orig;
>       /* ... */
>   }
>
> Like Robert showed, if it's already frozen then the key is untouched (no 
> dup+freeze).
>
> The docs could be made clearer: An _unfrozen_ String passed as a key 
> will be duplicated and frozen.

That doesn't answer my question. I showed that dup+freeze did not
adversely affect TestStr (i.e. dupstr was still accessible), so
something else is going on.

> -- 
> Posted via http://www.ruby-forum.com/.
>

-- 
Brian Adkins
http://www.lojic.com/
http://lojic.com/blog/