def visitExpr(self, ctx: DecafParser.ExprContext):
line_num = ctx.start.line
expr_type = ""
if len(ctx.expr()) == 2:
type_a = self.visit(ctx.expr(0))
type_b = self.visit(ctx.expr(1))
op = ctx.bin_op()
if type_a == type_b:
expr_type = type_a
else:
expr_type = None
#print('Error on line', line_num, 'type mismatched in expression')
#12
if (op.rel_op() != None or op.arith_op() != None
) and type_a != 'int' and type_b != 'int':
print('Error on line ' + str(line_num) +
' operands must be of type int')
#13
elif op.eq_op() != None and type_a != type_b:
print('Error on line ' + str(line_num) +
' operands must be of same type')
#14
elif op.cond_op() != None and (type_a != 'boolean'
or type_b != 'boolean'):
print('Error on line ' + str(line_num) +
' operands must be of type boolean')
elif ctx.location() != None:
var_name = ctx.location().ID().getText()
var_symbol = self.st.lookup(var_name)
if var_symbol != None:
expr_type = var_symbol.type
else:
#2
expr_type = None
print('Error on line ' + str(line_num) + ', ' + var_name +
' has not been declared')
elif ctx.data_literal() != None:
if ctx.data_literal().int_literal() != None:
expr_type = 'int'
elif ctx.data_literal().bool_literal() != None:
expr_type = 'boolean'
else:
expr_type = None
elif ctx.method_call() != None:
method_name = ctx.method_call().method_name().getText()
method_symbol = self.st.lookup(method_name)
if method_symbol != None:
expr_type = method_symbol.type
self.visit(ctx.method_call())
else:
method_symbol = None
elif ctx.EXCLAMATION() != None:
expr_type = self.visit(ctx.expr(0))
#14
if expr_type != 'boolean':
print('Error on line ' + str(line_num) +
' operand must be of type boolean')
else:
self.visitChildren(ctx)
return expr_type
def visitExpr(self, ctx: DecafParser.ExprContext):
line_number = ctx.start.line
method_call = ctx.method_call()
bin_oper = ""
if ctx.expr(0) != None:
if ctx.expr(0).bin_op() != None:
bin_oper = ctx.expr(0).bin_op().getText()
if self.eq_op:
pass
else:
expressions = ctx.expr(0)
if expressions != None:
if ctx.expr(0).location() and bin_oper != None:
for items in ctx.expr():
locatons = items.getText()
"""
check that the operands of bin_op are ints
"""
if self.st.lookup(locatons).type != "int":
print(
"ERROR: can only use a airthmetic operation on ints",
line_number)
if ctx.expr(0) and bin_oper != None:
if ctx.expr(0).location:
pass
else:
airth_op = ctx.expr(0).bin_op().airth_op().getText()
if airth_op in expressions.getText():
operands = ctx.expr(0).getText().replace(
airth_op, "")
listOfoperands = list(operands)
"""
if operands are not loctions (meaning not varibles), try to chnage the
type to int, if that fails throw error
"""
for i in range(len(listOfoperands)):
try:
int(listOfoperands[i])
except:
print(
"ERROR: can only use a airthmetic operation on ints",
line_number)
"""
check if a method call in side of an expression is not void as it must be a type to
be evaluated to something for it to be used in an expression, void is anon type
"""
method_expr_params = []
if method_call != None:
method_params = method_call.expr()
if self.st.lookup(method_call.ID().getText()).type == "void":
print(
"ERROR: for method to be used here, method must return something"
+ " line numnber", line_number)
if "()" in method_call.getText():
name = method_call.getText()
name = name.replace("()", "")
for names in method_params:
method_expr_params = method_expr_params.append[names]
if len(method_expr_params) < len(
self.st.lookup(name).params):
print(
"ERROR: " + "method " +
self.st.lookup(name).id + " epecting",
len(self.st.lookup(name).params), "but got",
len(method_expr_params), "on line", line_number)
return self.visitChildren(ctx)