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########################################################################
#
# File Name: NamedExpressions.py
#
#
"""
Versa variables
WWW: http://4suite.org/4RDF e-mail: support@4suite.org
Copyright 2001-2002 Fourthought Inc, USA.
See http://4suite.org/COPYRIGHT for license and copyright information
"""
import types
import DataTypes, CoreFunctions
from Ft.Xml.Lib.XmlString import XmlStrStrip, SplitQName
#FIXME: Move to Versa exception
from Ft.Rdf import RDF_MS_BASE, RDF_SCHEMA_BASE, OBJECT_TYPE_RESOURCE, OBJECT_TYPE_UNKNOWN
from Ft.Rdf.Parsers.Versa import g_extFunctions, RuntimeException
class VariableReference:
"""
A variable reference
"""
def __init__(self, expr):
self.expr = expr
return
def evaluate(self, con):
from Ft.Xml.XPath import Util
expanded = Util.ExpandQName(self.expr, namespaces=con.nsMapping)
try:
return con.varBindings[expanded]
except KeyError:
raise RuntimeException(RuntimeException.UNDEFINED_VARIABLE,
expanded[0], expanded[1])
def FunctionCallExprConstructor(name, args=None):
args = args or []
name = XmlStrStrip(name)
key = SplitQName(name)
count = len(args)
if count == 0:
return FunctionCall(name, key, args)
if count == 1:
return FunctionCall1(name, key, args)
if count == 2:
return FunctionCall2(name, key, args)
if count == 3:
return FunctionCall3(name, key, args)
return FunctionCallN(name, key, args)
class FunctionCall:
def __init__(self, name, key, args):
self._name = name
self._key = key
self._args = args
self._func = None
return
def pprint(self, indent=''):
print indent + str(self)
for arg in self._args:
arg.pprint(indent + ' ')
def error(self, *args):
raise Exception('Unknown function call: %s' % self._name)
def evaluate(self, context):
"""Call the function"""
if not self._func:
(prefix, local) = self._key
if prefix:
try:
expanded = (context.processorNss[prefix], local)
except:
raise RuntimeException(RuntimeException.UNDEFINED_PREFIX, prefix)
else:
expanded = self._key
self._func = (g_extFunctions.get(expanded) or
CoreFunctions.FUNCTIONS.get(expanded, self.error))
try:
result = self._func(context)
except TypeError, e:
if _IsExceptionForImmediatelyCalledFunc(e, self._func):
raise RuntimeException(RuntimeException.WRONG_ARGUMENTS, str(expanded), '')
raise
return result
def __getinitargs__(self):
return (self._name, self._key, self._args)
def __getstate__(self):
state = vars(self).copy()
del state['_func']
return state
def __str__(self):
return '<%s at %x: %s>' % (self.__class__.__name__, id(self), repr(self))
def __repr__(self):
result = self._name + '('
if len(self._args):
result = result + repr(self._args[0])
for arg in self._args[1:]:
result = result + ', ' + repr(arg)
return result + ')'
class FunctionCall1(FunctionCall):
def __init__(self, name, key, args):
FunctionCall.__init__(self, name, key, args)
self._arg0 = args[0]
return
def evaluate(self, context):
arg0 = self._arg0.evaluate(context)
if not self._func:
(prefix, local) = self._key
if prefix:
try:
expanded = (context.processorNss[prefix], local)
except:
raise RuntimeException(RuntimeException.UNDEFINED_PREFIX, prefix)
else:
expanded = self._key
self._func = (g_extFunctions.get(expanded) or
CoreFunctions.FUNCTIONS.get(expanded, self.error))
try:
result = self._func(context, arg0)
except TypeError, e:
if _IsExceptionForImmediatelyCalledFunc(e, self._func):
raise RuntimeException(RuntimeException.WRONG_ARGUMENTS, str(expanded), '')
raise
return result
class FunctionCall2(FunctionCall):
def __init__(self, name, key, args):
FunctionCall.__init__(self, name, key, args)
self._arg0 = args[0]
self._arg1 = args[1]
return
def evaluate(self, context):
arg0 = self._arg0.evaluate(context)
arg1 = self._arg1.evaluate(context)
if not self._func:
(prefix, local) = self._key
if prefix:
try:
expanded = (context.processorNss[prefix], local)
except:
raise RuntimeException(RuntimeException.UNDEFINED_PREFIX, prefix)
else:
expanded = self._key
self._func = (g_extFunctions.get(expanded) or
CoreFunctions.FUNCTIONS.get(expanded, self.error))
try:
result = self._func(context, arg0, arg1)
except TypeError, e:
if _IsExceptionForImmediatelyCalledFunc(e, self._func):
raise RuntimeException(RuntimeException.WRONG_ARGUMENTS, str(expanded), '')
raise
return result
class FunctionCall3(FunctionCall):
def __init__(self, name, key, args):
FunctionCall.__init__(self, name, key, args)
self._arg0 = args[0]
self._arg1 = args[1]
self._arg2 = args[2]
return
def evaluate(self, context):
arg0 = self._arg0.evaluate(context)
arg1 = self._arg1.evaluate(context)
arg2 = self._arg2.evaluate(context)
if not self._func:
(prefix, local) = self._key
if prefix:
try:
expanded = (context.processorNss[prefix], local)
except:
raise RuntimeException(RuntimeException.UNDEFINED_PREFIX, prefix)
else:
expanded = self._key
self._func = (g_extFunctions.get(expanded) or
CoreFunctions.FUNCTIONS.get(expanded, self.error))
try:
result = self._func(context, arg0, arg1, arg2)
except TypeError, e:
if _IsExceptionForImmediatelyCalledFunc(e, self._func):
raise RuntimeException(RuntimeException.WRONG_ARGUMENTS, str(expanded), '')
raise
return result
class FunctionCallN(FunctionCall):
def __init__(self, name, key, args):
FunctionCall.__init__(self, name, key, args)
return
def evaluate(self, context):
args = [context] + map(lambda x, c=context:
x.evaluate(c),
self._args)
if not self._func:
(prefix, local) = self._key
if prefix:
try:
expanded = (context.processorNss[prefix], local)
except:
raise RuntimeException(RuntimeException.UNDEFINED_PREFIX, prefix)
else:
expanded = self._key
self._func = (g_extFunctions.get(expanded) or
CoreFunctions.FUNCTIONS.get(expanded, self.error))
try:
result = apply(self._func, args)
except TypeError, e:
if _IsExceptionForImmediatelyCalledFunc(e, self._func):
raise RuntimeException(RuntimeException.WRONG_ARGUMENTS, str(expanded), '')
raise
return result
def _IsExceptionForImmediatelyCalledFunc(e, f):
i = str(e).find('(')
called_function_name = str(f).split()[1]
if i != -1 and str(e)[:i] == called_function_name:
return 1
return 0
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