def expect(self, tokens, level=0, debug=False):
index = tokens.getIndex()
exhausted = tokens.isExhausted()
error = "Value never instantiated!"
value = Serializer(False, None, error)
if debug:
print('\t' * level + "RHSTree.expect(), Type:",
self.levelType.name, "; Level:", level)
if self.levelKind == RHSKind.LEAF:
print('\t' * level + "NODE:", str(self.node))
print('\t' * level + "Before Index:", index)
print('\t' * level + "Before Exhaust:", exhausted)
print('\t' * level + "Current Token:", str(tokens.currentToken()))
if self.levelType == RHSType.TERMINAL:
if self.node.getValue() == '':
yield Serializer(True, '', None)
elif (not tokens.isExhausted()) and self.node.getValue(
) == tokens.currentToken().getValue():
tokens.nextToken()
yield Serializer(True, self.node.getValue(), None)
else:
error = "ERROR: Expected '" + str(
self.node.getValue()) + "', got: '" + str(
tokens.currentToken().getValue()) + "'"
elif self.levelType == RHSType.REGEX:
if (not tokens.isExhausted()) and self.node.isTypeOf(
tokens.currentToken().getValue()):
thisToken = tokens.currentToken().getValue()
tokens.nextToken()
yield Serializer(True, thisToken, None)
else:
error = "ERROR: Expected token of type: '" + str(
self.node.getName()) + "', got: '" + str(
tokens.currentToken().getValue()) + "'"
elif self.levelType == RHSType.IDENTIFIER:
for value in self.link.expectMatch(tokens, level + 1, debug):
if value:
yield value
tokens.setIndex(index, exhausted)
error = value.getError()
elif self.levelType == RHSType.GROUP:
for value in self.children[0].expect(tokens, level + 1, debug):
if value:
yield value
tokens.setIndex(index, exhausted)
error = value.getError()
elif self.levelType == RHSType.OPTIONAL:
# First try not parsing this. If the execution gets back to this point,
# then we need to actually use this option. Thus expect.
yield Serializer(True, '', None)
for value in self.children[0].expect(tokens, level + 1, debug):
if value:
yield value
tokens.setIndex(index, exhausted)
error = value.getError()
elif self.levelType == RHSType.REPEAT:
for value in self.expectRepeat(tokens, level, debug):
if value:
yield value
tokens.setIndex(
index,
exhausted) # this isn't in the loop because if repeat fails
# we typically want to try more tokens, not less
error = value.getError()
elif self.levelType == RHSType.CONCATENATION:
for value in self.expectConcat(tokens, 0, level + 1, debug):
if value:
yield value
tokens.setIndex(index, exhausted)
error = value.getError()
elif self.levelType == RHSType.ALTERNATION:
for child in self.children:
for value in child.expect(tokens, level + 1, debug):
if value:
yield value
tokens.setIndex(index, exhausted)
error = value.getError()
if debug:
print('\t' * level + "After Index:", tokens.getIndex())
print('\t' * level + "result:", False)
print('\t' * level + "Is Exhausted:", tokens.isExhausted())
print('\t' * level + 'Error:', str(error))
print('\t' * level + "value:", str(value), "\n")
yield Serializer(False, None, error)
