Re: Status of ayacc and aflex?

["Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de>]

On Fri, 22 Aug 2008 05:02:43 -0700 (PDT), Ludovic Brenta wrote:

> Speaking of lexical analysis and recursive descent parsers, I'd like
> to know whether anyone here has tried OpenToken[1] and would like to
> comment on it.
> 
> [1] http://www.telepath.com/~dennison/Ted/OpenToken/OpenToken.html

I studied it some time ago and found it interesting. In particular, I
borrowed the idea of generation of a table from an Ada enumeration type. If
a table contains only legal Ada identifiers, it is a very quick way to
create it.

To the critique of OpenToken. One problem is that it really concentrates on
tokens, nothing else. A recursive descent parser should also support
higher-level constructs, like user-defined blank/comment, identifier,
literals, and more generally expressions. So that, when you see the token
"declare", you could tell the parser get me a name, and then after the
colon, the declaration expression etc.

It also pays too little attention to abstracting the sources being parsed
and links to the sources (needed for error messages and integration into
IDE).

-- 
Regards,
Dmitry A. Kazakov
http://www.dmitry-kazakov.de