class TigrParser(AbstractParser):
def __init__(self, drawer, exception_handler):
super().__init__(drawer)
self.regex_pattern = r'(^[a-zA-Z]\b)\s+?(-?\b\d+\.?\d?\b)?\s*?([#|//].*)?$'
self.__output_log = []
self.exception_handler = exception_handler
try:
self.command_builder = CommandBuilder()
except Exception as e:
self.exception_handler.display_and_exit(e)
@property
def output_log(self):
# readonly
return self.__output_log
def parse(self, raw_source):
if type(
raw_source
) == str: # defensively handles edge case where a single command was passed as a string
raw_source = [raw_source]
for line_number in range(0, len(raw_source) - 1):
current_line = self.__prepare_line(raw_source[line_number])
if self.__is_line_blank(current_line):
continue
try:
command, data = self.__parse_line(current_line)
prepared_command = self.command_builder.prepare_command(
command, data)
output = prepared_command.execute(self.drawer)
self._log_drawer_output(output)
except Exception as e:
self.exception_handler.display_and_exit(
e, line_number=line_number, line=current_line)
def __prepare_line(self, line):
return line.strip()
def __is_line_blank(self, line):
return not line
def __parse_line(self, line):
match = re.findall(self.regex_pattern, line)
if match:
groups = match[0]
command = groups[0].upper()
if groups[1]:
data = int(round(float(groups[1])))
""" Parser accepts decimals but silently rounds them in the background - all numbers passed are
stored as integers"""
else:
data = None
return command, data
else:
raise SyntaxError(f"Invalid Syntax")
def _log_drawer_output(self, output):
self.__output_log.append(output)
