class Program(object):
def __init__(self, filename):
self.pascal_parser = Parser(filename)
self.symbol_table = dict()
self.symbol_address = 0
self.instructions = list()
def run(self, mode=1):
token = self.pascal_parser.get_next_token()
if token == TK_PROGRAM:
self.run_program_name()
if self.run_program() != TK_DOT:
raise ValueError("Invalid End. Requires period.")
self.run_comments()
#print "#END\n\n"
def run_program_name(self):
token = "None"
program_name = '#'
while token is not None and token != TK_SEMICOLON:
token = self.pascal_parser.get_next_token()
program_name += self.pascal_parser.current_word
#print program_name+'\n'
def run_program(self):
function_mode = None
while not self.pascal_parser.scanner.eof:
token = self.pascal_parser.get_next_token()
if token == TK_VAR:
self.pascal_parser.get_next_token()
function_mode = self.declare_variables
if token == TK_CONSTANT:
function_mode = self.run_default
if token == TK_FUNCTION:
function_mode = self.run_default
if token == TK_PROCEDURE:
function_mode = self.run_default
if token == TK_BEGIN:
self.run_begin()
token = self.pascal_parser.get_next_token()
return token
if not function_mode:
raise ValueError("Invalid Token: '%s'" % self.pascal_parser.print_token(token))
function_mode()
def run_default(self):
token = "None"
while token and token != TK_SEMICOLON:
token = self.pascal_parser.get_next_token()
#print "DEFAULT: %s" % token
return
def run_begin(self):
token = self.pascal_parser.get_next_token()
while token and token != TK_END:
if token == TK_IDENTIFIER:
self._assignment()
elif token == TK_WRITE:
self._write()
else:
print "Operation '%s': Not supported"
while self.pascal_parser.get_next_token() and \
self.pascal_parser.current_token != TK_SEMICOLON: pass
if self.pascal_parser.current_token != TK_SEMICOLON:
raise ValueError("Invalid Expression at '%s'" % self.pascal_parser.current_word)
token = self.pascal_parser.get_next_token()
return
def _assignment(self):
word = self.pascal_parser.current_word
assignment = self.symbol_table.get(word, None)
if not assignment:
raise ValueError("Identifier does not exist: '%s'" % word)
if self.pascal_parser.get_next_token() != TK_ASSIGNMENT:
raise ValueError("Expected Assignment: Got %s" %
self.pascal_parser.current_word)
self.pascal_parser.get_next_token()
result = evaluate_expression(self.pascal_parser, self.symbol_table)
handle_int_real_conversion(assignment['data_type'], result[0], assignment=True)
assignment['value'] = result[1]
OutputBuffer.add("pusha %s" % assignment['address'])
def _write(self):
if self.pascal_parser.get_next_token() != TK_LEFT_PAREN:
raise ValueError("Expected '(': Got '%s'" % self.pascal_parser.current_word)
evaluate_expression(self.pascal_parser, self.symbol_table)
OutputBuffer.add("write")
def run_comments(self):
while not self.pascal_parser.scanner.eof:
token = self.pascal_parser.get_next_token()
print "COMMENTS: %s" % token
def declare_variables(self):
var_list = self.get_var_list()
result_props = get_identifier_props(self.pascal_parser)
for var_name in var_list:
if var_name in self.symbol_table:
raise ValueError("Identifier already exists: '%s'" % var_name)
var_entry = {var_name: dict(result_props)}
var_entry[var_name]['address'] = self.symbol_address
var_entry[var_name]['var_name'] = var_name
self.symbol_address += var_entry[var_name]['size']
self.symbol_table.update(var_entry)
def get_var_list(self):
var_list = list()
token = self.pascal_parser.current_token
while True:
word = self.pascal_parser.current_word
if token != TK_IDENTIFIER:
raise ValueError("Unexpected Identifier, got '%s'" % word)
var_list.append(word)
token = self.pascal_parser.get_next_token()
if token == TK_COLON:
return var_list
elif token != TK_COMMA:
word = self.pascal_parser.current_word
raise ValueError("Invalid Token: '%s'. Expected comma or colon" % word)
token = self.pascal_parser.get_next_token()
def __init__(self, filename):
self.pascal_parser = Parser(filename)
self.symbol_table = dict()
self.symbol_address = 0
self.instructions = list()
def test_real_token(self):
file_name = "tests/mock_pas/reals.pas"
pascal_parser = Parser(file_name)
pascal_parser.get_next_token()
pascal_parser.is_real()
self.assertEquals(pascal_parser.current_word, '1.75')