From: Joel VanderWerf <vjoel@...>
Date: 2004-06-01T04:43:06+09:00
Subject: clarify README.EXT regarding symbols


I'd like to propose a clarification for README.EXT, after forgotting
(again) that symbols can be represented as ID and as VALUEs. What I 
forgot was that you have to use ID2SYM to convert ID -> VALUE. 
README.EXT doesn't mention this.

The original text is quoted below, followed by my proposed addition 
(maybe it would be better in different part of the file, possibly 
section 1.4):

> 2.2.2 ID or Symbol
> 
> You can invoke methods directly, without parsing the string.  First I
> need to explain about symbols (whose data type is ID).  ID is the
> integer number to represent Ruby's identifiers such as variable names.
> It can be accessed from Ruby in the form:
> 
>  :Identifier
> 
> You can get the symbol value from a string within C code by using
> 
>   rb_intern(const char *name)

The ID of a symbol is not the same as the ruby VALUE that represents the
symbol as an object. If you want this VALUE, use the ID2SYM macro:

   ID id_sym = rb_intern("a_symbol");
   VALUE val_sym = ID2SYM(id);