2006-03-10  Morten Welinder  <terra@gnome.org>

	* src/expr.h (GnmExprTop): New type for top-level expressions.
	* src/clipboard.h (GnmCellCopy): Use a top-level expression here.
	Rename it to "texpr" to make sure we catch all users.  All users
	changed.
	* src/dependent.h (GnmDependent): Ditto.
	* src/expr-name.h (GnmNamedExpr): Ditto.
	* src/style-conditions.h (GnmStyleCond): Ditto.
	* src/validation.h (GnmValidation): Ditto.

	* src/expr.c (gnm_expr_top_new, gnm_expr_top_new_constant,
	gnm_expr_top_ref, gnm_expr_top_unref, gnm_expr_top_unwrap,
	gnm_expr_top_is_shared, gnm_expr_top_is_err,
	gnm_expr_top_is_rangeref, gnm_expr_top_get_constant,
	gnm_expr_top_contains_subtotal, gnm_expr_top_referenced_sheets,
	gnm_expr_top_first_funcall, gnm_expr_top_get_boundingbox,
	gnm_expr_top_rewrite, gnm_expr_top_get_ranges, gnm_expr_top_equal,
	gnm_expr_top_as_string, gnm_expr_top_as_gstring,
	gnm_expr_top_eval, gnm_expr_top_get_ranges): New functions.  Many
	non-top versions made static.
	(gnm_expr_copy): New function replacing gnm_expr_ref.  (Still
	simply refs, but not for long.)

	*/*.c: Massive changes adapting to the above.