def createAction(self, statementGroup):
'''Tries to create an action based on p_statementGroup. If the statement
is not correct, r_ is -1. Else, r_ is the index of the element within
the buffer that is the object of the action.'''
res = -1
try:
# Check the whole statement group
if not statementGroup or (len(statementGroup) > 2):
raise ParsingError(BAD_STATEMENT_GROUP % str(statementGroup))
# Check the statement
statement = statementGroup[0]
aRes = self.actionRex.match(statement)
if not aRes:
raise ParsingError(BAD_STATEMENT % statement)
statementName, podElem, minus, actionType, subExpr = aRes.groups()
if not (podElem in PodElement.POD_ELEMS):
raise ParsingError(BAD_ELEMENT % podElem)
if minus and (not podElem in PodElement.MINUS_ELEMS):
raise ParsingError(BAD_MINUS %
(podElem, PodElement.MINUS_ELEMS))
indexPodElem = self.getIndex(podElem)
if indexPodElem == -1:
raise ParsingError(
ELEMENT_NOT_FOUND % (podElem, str([
e.__class__.__name__.lower() \
for e in self.elements.values()])))
podElem = self.elements[indexPodElem]
# Check the 'from' clause
fromClause = None
source = 'buffer'
if len(statementGroup) > 1:
fromClause = statementGroup[1]
source = 'from'
if not fromClause.startswith('from '):
raise ParsingError(BAD_FROM_CLAUSE % fromClause)
fromClause = fromClause[5:]
# Create the action
if actionType == 'if':
self.action = IfAction(statementName, self, subExpr, podElem,
minus, source, fromClause)
self.env.ifActions.append(self.action)
if self.action.name:
# We must register this action as a named action
if self.env.namedIfActions.has_key(self.action.name):
raise ParsingError(DUPLICATE_NAMED_IF)
self.env.namedIfActions[self.action.name] = self.action
elif actionType == 'else':
if not self.env.ifActions:
raise ParsingError(ELSE_WITHOUT_IF)
# Does the "else" action reference a named "if" action?
ifReference = subExpr.strip()
if ifReference:
if not self.env.namedIfActions.has_key(ifReference):
raise ParsingError(ELSE_WITHOUT_NAMED_IF % ifReference)
linkedIfAction = self.env.namedIfActions[ifReference]
# This "else" action "consumes" the "if" action: this way,
# it is not possible to define two "else" actions related to
# the same "if".
del self.env.namedIfActions[ifReference]
self.env.ifActions.remove(linkedIfAction)
else:
linkedIfAction = self.env.ifActions.pop()
self.action = ElseAction(statementName, self, None, podElem,
minus, source, fromClause,
linkedIfAction)
elif actionType == 'for':
forRes = MemoryBuffer.forRex.match(subExpr.strip())
if not forRes:
raise ParsingError(BAD_FOR_EXPRESSION % subExpr)
iter, subExpr = forRes.groups()
self.action = ForAction(statementName, self, subExpr, podElem,
minus, iter, source, fromClause)
elif actionType == 'with':
variables = self._getVariables(subExpr)
self.action = VariablesAction(statementName, self, podElem,
minus, variables, source,
fromClause)
else: # null action
if not fromClause:
raise ParsingError(NULL_ACTION_ERROR)
self.action = NullAction(statementName, self, None, podElem,
None, source, fromClause)
res = indexPodElem
except ParsingError, ppe:
PodError.dump(self, ppe, removeFirstLine=True)
