Re: implementing data tags via object properties -- help with debugging?

[robertb@continuumsi.com]

I guess you are right.  I may as well use global variables (in the form of
"static", local in each file).  Eventually, the right thing would be for
each procedure to take a "Library" as an argument -- the "global" space
(such as it is) would then be relegated to the Scheme world in that case.

By the way, I did look in the PGRT and it does use global variables (like for
Display, etc.).  So, I suppose, with embedding, this may be a necessary
evil.

Thanks for your help, all!

 > From: thi <ttn@mingle.glug.org>
 > Date: Fri  May  7, 10:13am
 >
 > robertb@continuumsi.com writes:
 > 
 >  >  > one immediately apparent problem is using `gh_eval_str'.  you
 >  >  > probably want to simply save the return value of
 >  >  > `gh_new_procedure', an SCM.
 >  > 
 >  > Well, doing that defeats the purpose of trying not to have global
 >  > variables!  Perhaps I was too idealist to believe that I could avoid
 >  > use of global variables in Guile.  It was so easy in X-Windows!
 > 
 > in your example, does this code
 > 
 >    gh_set_ext_data(gh_new_procedure1_0("ReadSymbols", ServerReadSymbols),
 >                    (void*)lib);
 > 
 > get called multiply?  each `gh_new_procedure1_0' call returns a new
 > procedure object.
 > 
 > `ServerReadSymbols' is already global in the C function namespace and
 > "ReadSymbols" is already global in the string pool.  you are starting
 > with global data and then calling a function that gives you a new
 > pointer each time called.  probably you will want to emulate libguile
 > practice of making `ServerReadSymbols' file static and then in the init
 > procedure (called only once), saving the SCM.  then you can pass this
 > SCM around w/ resorting to `gh_eval_str' (which consults yet another
 > global namespace...).
 > 
 > thi

 > From: Greg Harvey <Greg.Harvey@thezone.net>
 > Date: Fri  May  7,  2:47pm
 >
[message discarded]
 >
 > -- 
 > Greg



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