def condChecker(self, line, stmt, expr):
if expr != _boolean:
ErrorHandler.typeError(line, stmt, 2)
self.error()
return _error
return _boolean
def intChecker(self, line, leftType, rightType, op):
if leftType != _int or rightType != _int:
ErrorHandler.typeError(line, op)
self.error()
return _error
return _int
def visitAsignStmt(self, ctx: decafParser.AsignStmtContext):
leftType = self.visit(ctx.location())
rightType = self.visit(ctx.expression())
if not leftType == rightType:
ErrorHandler.typeError(ctx.start.line, "=")
self.error()
def visitMethodCall(self, ctx: decafParser.MethodCallContext):
name = ctx.ID().getText()
methodSymbol = self.currentScope.resolve(name)
# Check that the symbol is defined
if not methodSymbol:
ErrorHandler.nameError(ctx.start.line, name)
self.error()
# Check that the symbol is a method
isMethod = isinstance(methodSymbol, symtab.MethodSymbol)
if not isMethod:
ErrorHandler.typeError(ctx.start.line, name, 3)
self.error()
# Check method signature
signature = methodSymbol.args
args = list()
for arg in ctx.arg():
type = self.visit(arg)
args.append(type)
if not (signature == args):
ErrorHandler.typeError(ctx.start.line, name, 4)
self.error()
# Return the type of the method
# to be able to make methods calls from conditional statements
return methodSymbol.type.name
def visitLocation(self, ctx: decafParser.LocationContext):
name = ctx.ID().getText()
symbol = self.currentScope.resolve(name)
if not symbol:
ErrorHandler.nameError(ctx.start.line, name)
self.error()
return _error
# Check if it is a built-in type
builtIn = False
if symbol.type.name in self.T.builtIn:
builtIn = True
if builtIn:
# Declared as a variable
if isinstance(symbol, symtab.VariableSymbol):
if ctx.expr is not None:
ErrorHandler.typeError(ctx.start.line, symbol.name, 5)
self.error()
if ctx.loc is not None:
ErrorHandler.attributeError(ctx.start.line, symbol.name,
ctx.loc.getText())
self.error()
return symbol.type.name
# Declared as an array
elif isinstance(symbol, symtab.ArraySymbol):
try:
index = int(ctx.expr.getText())
except ValueError:
index = None
if (index is None) or (index < 0) or (index >= int(
symbol.num)):
ErrorHandler.arrayError(ctx.start.line, symbol.name, 2)
self.error()
if ctx.loc is not None:
ErrorHandler.attributeError(ctx.start.line, symbol.name,
ctx.loc.getText())
self.error()
return symbol.type.name
if not builtIn:
# Save the actual scope
actualScope = self.currentScope
# Because it has a member, we declare the struct as the current scope
self.currentScope = self.structs.get(symbol.type.name)
# Visit location
type = self.visit(ctx.loc)
# Restore actual scope
self.currentScope = actualScope
# Return the type of the location
return type
def visitNegExp(self, ctx: decafParser.NegExpContext):
exprType = self.visit(ctx.expression())
if exprType != _boolean:
ErrorHandler.typeError(ctx.start.line, '!')
self.error()
return _error
return _boolean
def visitMinExp(self, ctx: decafParser.MinExpContext):
exprType = self.visit(ctx.expression())
if exprType != _int:
ErrorHandler.typeError(ctx.start.line, '-')
self.error()
return _error
return _int
def visitCondExp(self, ctx: decafParser.CondExpContext):
op = ctx.op.getText()
leftType = self.visit(ctx.left)
rightType = self.visit(ctx.right)
if leftType != _boolean or rightType != _boolean:
ErrorHandler.typeError(ctx.start.line, op)
self.error()
return _error
return _boolean
def visitEqExp(self, ctx: decafParser.EqExpContext):
op = ctx.op.getText()
eq = [_int, _char, _boolean]
leftType = self.visit(ctx.left)
rightType = self.visit(ctx.right)
if leftType != rightType:
ErrorHandler.typeError(ctx.line.start, op)
self.error()
return _error
if (leftType not in eq) or (rightType not in eq):
ErrorHandler.typeError(ctx.line.start, op)
self.error()
return _error
return _boolean
