############################################################################## # # Copyright (c) 2002 Nexedi SARL and Contributors. All Rights Reserved. # Jean-Paul Smets-Solanes <jp@nexedi.com> # # WARNING: This program as such is intended to be used by professional # programmers who take the whole responsability of assessing all potential # consequences resulting from its eventual inadequacies and bugs # End users who are looking for a ready-to-use solution with commercial # garantees and support are strongly adviced to contract a Free Software # Service Company # # This program is Free Software; you can redistribute it and/or # modify it under the terms of the GNU General Public License # as published by the Free Software Foundation; either version 2 # of the License, or (at your option) any later version. # # This program is distributed in the hope that it will be useful, # but WITHOUT ANY WARRANTY; without even the implied warranty of # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the # GNU General Public License for more details. # # You should have received a copy of the GNU General Public License # along with this program; if not, write to the Free Software # Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. # ############################################################################## from Interface import Interface class Predicate(Interface): """ A Predicate allows to make a statement about a document. A statement can be related to: - the attributes of the document (ex. price >= 3.0) - the categories of the document (ex. ) The Predicate class is an abstract class, which is implemented by subclasses. """ def test(context, tested_base_category_list=None): """A Predicate can be tested on a given context. Parameters can passed in order to ignore some conditions: - tested_base_category_list: this is the list of category that we do want to test. For example, we might want to test only the destination or the source of a predicate. """ def asSQLExpression(): """ A Predicate can be rendered as an sql expression. This can be useful to create reporting trees based on the ZSQLCatalog """