Re: LANG: Dynamic characteristics

John W. Barrus (
Thu, 14 Jul 1994 12:13:50 -0400

At 11:32 AM 7/14/94 -0400, Mark Waks wrote:
>Now Inventor *does* have roughly the same view of the world as Geomview, but
>unfortunately the language it is intended for is C++. It's *quite*
>clear to me that any dialect of C would be a mistake -- it's simply
>too much work to parse. So I'm not really in favor of picking up
>Inventor completely wholesale.

Mark, I'm not sure what you mean about the Inventor language being too
difficult to parse.

I wrote a file format about 3 weeks ago for a project I am currently
working on. It seemed fairly complex, but complete. I have a student
working for me who _learned_ lex and yacc _and_ wrote the lex and yacc (.l
and .y) input files to read in and create data structures from my data file
in about 2 weeks.

Although I don't know lex and yacc myself, this would indicate to me that
it probably won't be too hard to write a program to read in a file and
convert it to an in-memory data structure (C or C++) no matter what the
format is. If it is written in C, then no one else has to write it again
(hopefully just small modifications for different systems).

In other words, I no longer think that parsing is the problem. Perhaps I
misunderstood your comment?

By the way, I don't propose that we pick up Inventor wholesale either, just
the relevant parts.

John B.


John Barrus Research Scientist

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