def parse(self, input_tape: str) -> List[object]:
self.stack.clear()
current_state = self.start_state
input_tape_index = 0
for input_char in input_tape:
try:
configuration = Configuration(current_state, input_char)
transition = self._find_transition(configuration)
current_state = self._apply_transition(transition,
configuration)
input_tape_index += 1
except ParsingError as error:
print('State:', current_state.name)
print('Index:', input_tape_index)
print('Original Input:', input_tape)
raise error
if current_state not in self.accept_states:
print('State:', current_state.name)
raise ParsingError(
f'Parser was not in a final state after the input tape was read.'
)
return self.stack.data_stack[:]
def perform_stack_action(self, stack: AutomatonStack,
configuration: Configuration):
current_content = stack.get_current_content()
if not current_content:
raise ParsingError('A variable name was expected!')
stack.add_data(Argument(current_content))
stack.remove_level()
def perform_stack_action(self, stack: AutomatonStack,
configuration: Configuration):
current_content = stack.get_current_content()
if not current_content:
raise ParsingError('Empty function name is not allowed!')
stack.add_data(FunctionDeclaration(current_content))
stack.remove_level()
stack.add_level()
def get_output_configuration(
self, input_configuration: Configuration) -> Configuration:
if not input_configuration.character.isalpha(
) and input_configuration.character != '_':
raise ParsingError(
f'Non-alpha character "{input_configuration.character}" detected.'
)
return Configuration(ArgumentState(), input_configuration.character)
def perform_stack_action(self, stack: AutomatonStack,
input_configuration: Configuration):
raise ParsingError(
'Expected a string on the right side of the constraint!')
def get_output_configuration(
self, input_configuration: Configuration) -> Configuration:
raise ParsingError(
'Expected a string on the right side of the constraint!')
def perform_stack_action(self, stack: AutomatonStack,
input_configuration: Configuration):
raise ParsingError(
'Expected an operator for the constraint (e.g. "=")!')
def get_output_configuration(
self, input_configuration: Configuration) -> Configuration:
raise ParsingError(
'Received a character after the function declaration ended.')
def get_current_content(self) -> str:
if not self.levels:
raise ParsingError('No more levels left on the stack')
return ''.join(self.levels[-1])
def perform_stack_action(self, stack: AutomatonStack,
input_configuration: Configuration):
raise ParsingError(
'Received a character after the code environment was closed.')
def perform_stack_action(self, stack: AutomatonStack, input_configuration: Configuration):
raise ParsingError('Expected the end of the constraint or a conjunctive "&"!')
def get_output_configuration(self, input_configuration: Configuration) -> Configuration:
raise ParsingError('Expected the end of the constraint or a conjunctive "&"!')
def perform_stack_action(self, stack: AutomatonStack,
input_configuration: Configuration):
raise ParsingError('An NLG message must start with a quotation mark!')
def get_output_configuration(
self, input_configuration: Configuration) -> Configuration:
raise ParsingError('An NLG message must start with a quotation mark!')
def perform_stack_action(self, stack: AutomatonStack,
input_configuration: Configuration):
raise ParsingError(
'Received a character after the function declaration ended.')
def get_output_configuration(
self, input_configuration: Configuration) -> Configuration:
raise ParsingError(
'The python code environment requires two closing braces!')
def get_output_configuration(
self, input_configuration: Configuration) -> Configuration:
ParsingError(
f'Unexpected character "{input_configuration.character}" after '
f'the expression ended.')
def perform_stack_action(self, stack: AutomatonStack,
configuration: Configuration):
raise ParsingError(
'The python code environment requires two closing braces!')
def _find_default_transition(self, current_state: State):
if current_state not in self.state_default_transition_mapping:
raise ParsingError(
f'No default transition found for state {current_state.name}.')
return self.state_default_transition_mapping.get(current_state, None)
def get_output_configuration(
self, input_configuration: Configuration) -> Configuration:
raise ParsingError(
'Received a character after the code environment was closed.')
def get_output_configuration(
self, input_configuration: Configuration) -> Configuration:
if input_configuration.character != '$':
raise ParsingError(
'Received a character after the NLG message ended.')
def add_char(self, stack_char: str):
if not self.levels:
raise ParsingError('No more levels left on the stack')
self.levels[-1].append(stack_char)
def get_output_configuration(
self, input_configuration: Configuration) -> Configuration:
raise ParsingError(
'Expected an operator for the constraint (e.g. "=")!')
def remove_level(self):
if not self.levels:
raise ParsingError('No more levels to remove from the stack')
self.levels.pop()
def perform_stack_action(self, stack: AutomatonStack,
input_configuration: Configuration):
if input_configuration.character != '$':
raise ParsingError(
'Received a character after the NLG message ended.')