2002-03-28  Jon K Hellan  <hellan@acm.org>

	* plugin.c (gnm_guile_helper): New function. Helper to call
	scm_apply_0.
	(gnm_guile_catcher): New function. Receives error info from Guile
	if Guile throws an error.
	(func_marshal_func): Handle errors from Guile gracefully. The old
	behaviour was to abort Gnumeric.

	* gnumeric_startup.scm (gnm:error->string): New function. Returns
	a string with Guile's error message.