Viewing file:  Context.py (3.13 KB) -rw-r--r--
Select action/file-type:
 (+) |  (+) |  (+) | Code (+) | Session (+) |  (+) | SDB (+) |  (+) |  (+) |  (+) |  (+) |  (+) |
########################################################################
# $Header: /var/local/cvsroot/4Suite/Ft/Xml/XPath/Context.py,v 1.11 2005/03/06 11:20:37 mbrown Exp $
"""
The context of an XPath expression
Copyright 2005 Fourthought, Inc. (USA).
Detailed license and copyright information: http://4suite.org/COPYRIGHT
Project home, documentation, distributions: http://4suite.org/
"""
from types import ModuleType
import CoreFunctions, BuiltInExtFunctions
from Ft.Xml import XML_NAMESPACE
__all__ = ['Context']
class Context:
functions = CoreFunctions.CoreFunctions.copy()
functions.update(BuiltInExtFunctions.ExtFunctions)
currentInstruction = None
def __init__(self,
node,
position=1,
size=1,
varBindings=None,
processorNss=None,
extModuleList=None,
extFunctionMap=None):
self.node = node
self.position = position
self.size = size
self.varBindings = varBindings or {}
self.processorNss = processorNss or {}
self.processorNss.update({'xml': XML_NAMESPACE})
self._documentIndex = {}
# This may get mutated during processing
functions = self.functions.copy()
# Search the extension modules for defined functions
if extModuleList:
for module in extModuleList:
if module:
if not isinstance(module, ModuleType):
module = __import__(module, {}, {}, ['ExtFunctions'])
if hasattr(module, 'ExtFunctions'):
functions.update(module.ExtFunctions)
# Add functions given directly
if extFunctionMap:
functions.update(extFunctionMap)
self.functions = functions
return
def __repr__(self):
return "<Context at 0x%x: Node=%s, Postion=%d, Size=%d>" % (
id(self), self.node, self.position, self.size)
def addFunction(self, expandedName, function):
if not callable(function):
raise TypeError("function must be a callable object")
self.functions[expandedName] = function
return
# Used for SortDocOrder with a nodeset containing multiple documents
def addDocument(self, document):
if document not in self._documentIndex:
self._documentIndex[document] = len(self._documentIndex)
return
# Used for SortDocOrder with a nodeset containing multiple documents
def compareDocuments(self, a, b):
# Make sure the documents we are comparing have an index
a = self._documentIndex.setdefault(a, len(self._documentIndex))
b = self._documentIndex.setdefault(b, len(self._documentIndex))
return cmp(a, b)
def copy(self):
return (self.node, self.position, self.size)
def set(self, state):
self.node, self.position, self.size = state
return
def clone(self):
newobj = self.__class__(self, self.node, self.position, self.size)
newobj.varBindings = self.varBindings.copy()
newobj.processorNss = self.processorNss.copy()
return newobj
|