def __bconnct(self, boolNode):
if self.current_token.tokentype == token.AND:
boolNode.bool_connector = self.current_token
self.__advance()
boolNode.rest = ast.BoolExpr()
self.__bexpr(boolNode.rest)
# if boolNode.rest.first_expr != None:
# boolNode.first_expr = boolNode.rest
elif self.current_token.tokentype == token.OR:
boolNode.bool_connector = self.current_token
self.__advance()
boolNode.rest = ast.BoolExpr()
self.__bexpr(boolNode.rest)
def __bconnct(self, bexpr_node):
temp_bool_expr = ast.BoolExpr()
if (self.current_token.tokentype == token.AND
or self.current_token.tokentype == token.OR):
bexpr_node.bool_connector = self.current_token
self.__advance()
self.__bexpr(temp_bool_expr)
bexpr_node.rest = temp_bool_expr
def __while(self):
while_node = ast.WhileStmt()
while_node.bool_expr = ast.BoolExpr()
self.__bexpr(while_node.bool_expr)
while_node.stmt_list = ast.StmtList()
self.__eat(token.DO, "expecting do")
self.__bstmts(while_node.stmt_list)
self.__eat(token.END, "expecting end")
return while_node
def __cond(self):
if_node = ast.IfStmt()
basic_if_node = ast.BasicIf()
basic_if_node.bool_expr = ast.BoolExpr()
basic_if_node.stmt_list = ast.StmtList()
self.__bexpr(basic_if_node.bool_expr)
self.__eat(token.THEN, "expecting then")
self.__bstmts(basic_if_node.stmt_list)
if_node.if_part = basic_if_node
self.__condt(if_node)
self.__eat(token.END, "expecting end")
return if_node
def __bexpr(self, boolNode):
if self.current_token.tokentype == token.NOT:
boolNode.negated = True
self.__advance()
self.__bexpr(boolNode)
self.__bexprt(boolNode)
elif self.current_token.tokentype == token.LPAREN:
self.__advance()
boolNode.first_expr = ast.BoolExpr()
self.__bexpr(boolNode.first_expr)
self.__eat(token.RPAREN, 'expecting )')
self.__bconnct(boolNode)
else:
boolNode.first_expr = self.__expr()
self.__bexprt(boolNode)
def __bexpr(self):
bool_expr_node = ast.BoolExpr()
if self.current_token.tokentype == token.NOT:
bool_expr_node.negated = True
self.__advance()
bool_expr_node = self.__bexpr()
self.__bexprt(bool_expr_node)
elif self.current_token.tokentype == token.LPAREN:
self.__advance()
bool_expr_node.first_expr = self.__bexpr()
self.__eat(token.RPAREN, 'expecting rparren')
self.__bconnct(bool_expr_node)
else:
bool_expr_node.first_expr = self.__expr()
self.__bexprt(bool_expr_node)
return bool_expr_node
def __condt(self, if_node):
if_node.else_stmts = ast.StmtList()
basic_if_node = ast.BasicIf()
basic_if_node.bool_expr = ast.BoolExpr()
if self.current_token.tokentype == token.ELIF:
basic_if_node.stmt_list = ast.StmtList()
self.__advance()
self.__bexpr(basic_if_node.bool_expr)
self.__eat(token.THEN, "expecting then")
self.__bstmts(basic_if_node.stmt_list)
if_node.elseifs.append(basic_if_node)
self.__condt(if_node)
elif self.current_token.tokentype == token.ELSE:
if_node.has_else = True
self.__advance()
self.__bstmts(if_node.else_stmts)
def __bexpr(self, bexpr_node):
if self.current_token.tokentype == token.NOT:
bexpr_node.negated = True
self.__advance()
self.__bexpr(bexpr_node)
self.__bexprt(bexpr_node)
elif self.current_token.tokentype == token.LPAREN:
bexpr_node.first_expr = ast.BoolExpr()
self.__advance()
# in this specific instance bexpr_node.first_expr must be a Bool expr
self.__bexpr(bexpr_node.first_expr)
self.__eat(token.RPAREN, "expecting ')'")
self.__bconnct(bexpr_node)
else:
bexpr_node.first_expr = self.__expr()
self.__bexprt(bexpr_node)
def __bexpr(self):
"""<bexpt> ::= <expr> <bexprt> | NOT <bexpr> <bexprt> |"""
""" LPAREN <bexpr> RPAREN <bconnct>"""
bool_expr_node = ast.BoolExpr()
if self.current_token.tokentype == token.LPAREN:
self.__advance()
bool_expr_node.first_expr = self.__bexpr()
self.__eat(token.RPAREN, 'expecting a ")"')
self.__bconnct(bool_expr_node)
elif self.current_token.tokentype == token.NOT:
self.__advance()
bool_expr_node.first_expr = self.__bexpr()
bool_expr_node.negated = True
self.__bexprt(bool_expr_node)
else:
bool_expr_node.first_expr = self.__expr()
self.__bexprt(bool_expr_node)
return bool_expr_node
def __bexpr(self):
boolStmt = ast.BoolExpr()
"""<bexpr> ::= <expr><bexprt>| NOT <bexpr><bexprt> | LPAREN <bexpr> RPAREN <bconnct>"""
temp = self.current_token.tokentype
if temp == token.NOT:
self.__advance()
boolStmt = self.__bexpr()
boolStmt.negated = True
self.__bexprt(boolStmt)
elif temp == token.LPAREN:
self.__advance()
boolStmt = self.__bexpr()
self.__eat(token.RPAREN, "expecting a ')'")
self.__bconnct(boolStmt)
else:
boolStmt.first_expr = self.__expr()
self.__bexprt(boolStmt)
return boolStmt
def __bexpr(self):
# print("bexpr: " + str(self.current_token))
bool_expr_node = ast.BoolExpr()
if self.current_token.tokentype == token.NOT:
bool_expr_node.negated = True
self.__advance() # eat NOT (we already know from 2 lines up)
bool_expr_node.first_expr = self.__bexpr()
bool_expr_node = self.__bexprt(bool_expr_node)
elif self.current_token.tokentype == token.LPAREN:
self.__advance() # eat LPAREN (we already know from 1 line up)
bool_expr_node.first_expr = self.__bexpr()
self.__eat(token.RPAREN, 'expected ")"')
# fine to not fill bool_rel and second_expr, they're optional
bool_expr_node = self.__bconnct(bool_expr_node)
else:
bool_expr_node.first_expr = self.__expr()
bool_expr_node = self.__bexprt(bool_expr_node)
return bool_expr_node
def __bexpr(self):
"""<bexpr> ::= <expr> <bexprt> | NOT <bexpr> <bexprt> | LPAREN <bexpr> RPAREN <bconnct>"""
bexpr = ast.BoolExpr()
if self.current_token.tokentype == token.LPAREN:
self.__eat(token.LPAREN, "Expected expression")
bexpr = self.__bexpr()
self.__eat(token.RPAREN, "Expected RPAREN token")
self.__bconnct(bexpr)
return bexpr
elif self.current_token.tokentype == token.NOT:
self.__eat(token.NOT, "Expected NOT token")
bexpr = self.__bexpr()
self.__bexprt(bexpr)
bexpr.negated = True
return bexpr
else:
bexpr.first_expr = self.__expr()
self.__bexprt(bexpr)
return bexpr
def __bexpr(self):
"""<bexpr> ::= <expr> <bexprt> | NOT <bexpr> <bexprt> | LPAREN <bexpr> RPAREN <bconnct> """
bexpr = ast.BoolExpr()
if self.__tokenIs(token.NOT):
bexpr.negated = True
self.__advance()
bexpr.first_expr = self.__bexpr()
self.__bexprt(bexpr)
elif self.__tokenIs(token.LPAREN):
bexpr.negated = False
self.__advance()
bexpr.first_expr = self.__bexpr()
self.__eat(token.RPAREN, "expected ')'")
self.__bconnct(bexpr)
else:
bexpr.negated = False
bexpr.first_expr = self.__expr()
self.__bexprt(bexpr)
return bexpr
