def unary_expr():
if SC.sym not in FIRSTUNARY_EXPR:
mark('invalid unary_expr first token')
if SC.sym in {PLUS, MINUS, NOT}:
getSym()
post_expr()
def rltn_expr():
if SC.sym not in FIRSTRLTN_EXPR:
mark('invalid rltn_expr first token')
add_expr()
while SC.sym in {LT, GT, LE, GE}:
getSym()
add_expr()
def add_expr():
if SC.sym not in FIRSTADD_EXPR:
mark('invalid add_expr first token')
mult_expr()
while SC.sym in {PLUS, MINUS}:
getSym()
mult_expr()
def mult_expr():
if SC.sym not in FIRSTMULT_EXPR:
mark('invalid mult_expr first token')
cast_expr()
while SC.sym in {MULT, DIV, MOD}:
getSym()
cast_expr()
def and_expr():
if SC.sym not in FIRSTAND_EXPR:
mark('invalid and_expr first token')
eqlty_expr()
while SC.sym == AND:
getSym()
eqlty_expr()
def expr():
if SC.sym not in FIRSTEXPR:
mark('invalid expr first token')
and_expr()
while SC.sym == OR:
getSym()
and_expr()
def cast_expr():
if SC.sym not in FIRSTCAST_EXPR:
mark('invalid cast_expr first token')
if SC.sym in {INT, FLOAT, STRING, BOOL}:
getSym()
if SC.sym == COLON: getSym()
else: mark("cast expects ':'")
unary_expr()
def eqlty_expr():
if SC.sym not in FIRSTEQLTY_EXPR:
if SC.sym == EQ:
mark("assignment requires ':='")
else:
mark('invalid eqlty_expr first token')
rltn_expr()
while SC.sym in {EQ, NE}:
getSym()
rltn_expr()
def stmt_list():
if SC.sym not in FIRSTSTMT_LIST:
mark('invalid stmt_list first token')
while SC.sym in {LINEEND} | FIRSTSTMT:
if SC.sym in FIRSTSTMT:
stmt()
elif SC.sym == LINEEND:
getSym()
else:
mark('unknown statement strt')
def post_expr():
if SC.sym not in FIRSTPOST_EXPR:
mark('invalid post_expr first token')
prime_expr()
while SC.sym in {INCC, DECC} | FIRSTPARAMS | FIRSTSELECTOR:
if SC.sym in {INCC, DECC}:
getSym()
elif SC.sym in FIRSTPARAMS:
params()
elif SC.sym in FIRSTSELECTOR:
selector()
def func_stmt():
if SC.sym not in FIRSTFUNC_STMT:
mark('invalid func_stmt first token')
if SC.sym == FUNCTION: getSym()
else: mark("expected 'define'")
if SC.sym == IDENT: getSym()
else: mark("expected identifier")
if SC.sym in FIRSTPARAMS: params()
else: mark("expected parameters")
if SC.sym in FIRSTSTMT: stmt()
else: mark("expected statement")
def program():
if SC.sym not in FIRSTPROGRAM:
mark('invalid program first token')
if SC.sym == PROGRAM: getSym()
else: mark("expected 'program'")
if SC.sym == IDENT: getSym()
else: mark("expected identifier")
if SC.sym in FIRSTPARAMS: params()
else: mark("expected parameters")
if SC.sym in FIRSTSTMT: stmt()
else: mark("expected statement")
def cplx_stmt():
if SC.sym not in FIRSTCPLX_STMT:
mark('invalid cplx_stmt first token')
if SC.sym == DO: getSym()
else: mark("expected 'do'")
if SC.sym == LINEEND: getSym()
else: mark("expected newline")
stmt_list()
if SC.sym == END: getSym()
else: mark("expected 'end'")
if SC.sym == LINEEND: getSym()
else: mark("expected newline")
def stmt():
if SC.sym not in FIRSTSTMT:
mark('invalid stmt first token')
if SC.sym in FIRSTCPLX_STMT:
cplx_stmt()
elif SC.sym in FIRSTEXPR_STMT:
expr_stmt()
elif SC.sym in FIRSTITER_STMT:
iter_stmt()
elif SC.sym in FIRSTSLCT_STMT:
slct_stmt()
elif SC.sym in FIRSTFUNC_STMT:
func_stmt()
elif SC.sym in FIRSTRETN_STMT:
retn_stmt()
elif SC.sym in FIRSTOUTP_STMT:
outp_stmt()
def prime_expr():
if SC.sym not in FIRSTPRIME_EXPR:
mark('invalid prime_expr first token')
if SC.sym == IDENT:
getSym()
elif SC.sym == INTEGER:
getSym()
elif SC.sym == REAL:
getSym()
elif SC.sym == STRING_LITERAL:
getSym()
elif SC.sym == LPAREN:
getSym()
expr()
if SC.sym == COMMA:
getSym()
expr()
if SC.sym == RPAREN: getSym()
else: mark("expected ')'")
else:
mark('expected expression')
def params():
if SC.sym not in FIRSTPARAMS:
mark('invalid selector first token')
if SC.sym == LPAREN: getSym()
else: mark("expected '('")
if SC.sym in FIRSTEXPR:
expr()
while SC.sym == COMMA:
getSym()
if SC.sym in FIRSTEXPR: expr()
else: mark("expected expression")
if SC.sym == RPAREN: getSym()
else: mark("expected ')'")
def selector():
if SC.sym not in FIRSTSELECTOR:
mark('invalid selector first token')
if SC.sym == LBRAK: getSym()
else: mark("expected '['")
if SC.sym in FIRSTEXPR:
expr()
while SC.sym == COMMA:
getSym()
if SC.sym in FIRSTEXPR: expr()
else: mark("expected expression")
if SC.sym == RBRAK: getSym()
else: mark("expected ']'")
def expr_stmt():
if SC.sym not in FIRSTEXPR_STMT:
mark('invalid expr_stmt first token')
assignment = False
if SC.sym in FIRSTPOST_EXPR:
post_expr()
if SC.sym == BECOMES:
getSym()
assignment = True
if assignment:
expr()
if SC.sym == LINEEND: getSym()
else: mark("expected newline")
else:
if SC.sym in BINARYOP:
# MIDWAY THROUGH EXPR, NEED TO PICKUP
# ASK: May break operator precidence
if SC.sym in {OR}:
expr()
elif SC.sym in {AND}:
and_expr()
elif SC.sym in {EQ, NE}:
eqlty_expr()
elif SC.sym in {LT, GT, LE, GE}:
rltn_expr()
elif SC.sym in {PLUS, MINUS}:
add_expr()
elif SC.sym in {MULT, DIV, MOD}:
mult_expr()
else:
mark('expected binary operator')
elif SC.sym == LINEEND:
# IF EXPRESSION IS A PRIME_EXPR w/ POSTFIX
pass
else:
mark('unknown expression state')
def outp_stmt():
if SC.sym not in FIRSTOUTP_STMT:
mark('invalid outp_stmt first token')
if SC.sym == OUTPUT: getSym()
else: mark("expected 'output'")
# errOpen = False
# if SC.sym == LPAREN: getSym()
# else: mark("output statement expects '('"); errOpen = True
if SC.sym in FIRSTEXPR: expr()
else: mark("expected expression")
# if SC.sym == RPAREN: getSym()
# else:
# if not errOpen: mark("expected ')'")
if SC.sym == LINEEND: getSym()
else: mark("expected newline")
def retn_stmt():
if SC.sym not in FIRSTRETN_STMT:
mark('invalid retn_stmt first token')
if SC.sym == RETURN: getSym()
else: mark("expected 'return'")
# if SC.sym == LPAREN:
# getSym()
if SC.sym in FIRSTEXPR:
expr()
# if SC.sym == RPAREN: getSym()
# else: mark("expected ')'")
elif SC.sym != LINEEND:
mark('return bracketed expression or none')
# if SC.sym == LINEEND: getSym()
else:
pass #mark("expected newline")
def slct_stmt():
if SC.sym not in FIRSTSLCT_STMT:
mark('invalid slct_stmt first token')
if SC.sym == IF: getSym()
else: mark("expected 'if'")
if SC.sym == LPAREN: getSym()
else: mark("if statement expects '('")
if SC.sym in FIRSTEXPR: expr()
else: mark("expected expression")
if SC.sym == RPAREN: getSym()
else: mark("expected ')'")
if SC.sym == LINEEND: getSym()
else:
if SC.sym in FIRSTSTMT: mark("expected stmt on newline")
else: mark("expected newline")
stmt()
if SC.sym == ELSE:
getSym()
if SC.sym == LINEEND: getSym()
else:
if SC.sym in FIRSTSTMT: mark("expected stmt on newline")
else: mark("expected newline")
if SC.sym in FIRSTSTMT: stmt()
else: mark("expected statement")
def iter_stmt():
if SC.sym not in FIRSTITER_STMT:
mark('invalid iter_stmt first token')
if SC.sym == WHILE: getSym()
else: mark("expected 'while'")
if SC.sym == LPAREN: getSym()
else: mark("while statement expects '('")
if SC.sym in FIRSTEXPR: expr()
else: mark("expected expression")
if SC.sym == RPAREN: getSym()
else: mark("expected ')'")
if SC.sym == LINEEND: getSym()
else:
if SC.sym in FIRSTSTMT: mark("expected stmt on newline")
else: mark("expected newline")
stmt()
