def visitNegationExpr(self, ctx: DecafParser.NegationExprContext):
t = self.visit(ctx.expression())
if t != type_enum.Boolean:
error = genericError('Can only negate (!) boolean expressions',
ctx.start.line)
self.errors.append(error)
return type_enum.Error
return type_enum.Boolean
def visitNegativeExpr(self, ctx: DecafParser.NegativeExprContext):
t = self.visit(ctx.expression())
if t != type_enum.Integer:
error = genericError(
'Can only apply negative (-) to integer expressions',
ctx.start.line)
self.errors.append(error)
return type_enum.Error
return type_enum.Integer
def visitAssignStmt(self, ctx: DecafParser.AssignStmtContext):
left_type = self.visit(ctx.left)
right_type = self.visit(ctx.right)
if right_type != left_type:
error = genericError(
'Can only assign to two expressions with the same type',
ctx.start.line)
self.errors.append(error)
return type_enum.Error
return type_enum.Boolean
def visitIfStmt(self, ctx: DecafParser.IfStmtContext):
self.enterScope('ifblock' + str(self.anonCounter), 'if')
self.anonCounter += 1
expt = self.TypeValidator.visit(ctx.expression())
if expt != type_enum.Boolean:
error = genericError('Expected boolean expression for if',
ctx.start.line)
self.TypeValidator.errors.append(error)
visit = self.visitChildren(ctx)
self.exitScope()
return visit
def visitEqualityOp(self, ctx: DecafParser.EqualityOpContext):
op = ctx.op.getText()
left_type = self.visit(ctx.left)
right_type = self.visit(ctx.right)
if right_type != left_type:
error = genericError(
'Can only apply %s to two expressions with the same type' % op,
ctx.start.line)
self.errors.append(error)
return type_enum.Error
return type_enum.Boolean
def visitLocation(self, ctx: DecafParser.LocationExprContext):
var_name = ctx.name.text
scope = self.scopes.peek()
var, _scope = scope.lookup(var_name)
value = type_enum.Error
if not var:
error = notDefinedError('Variable', var_name, ctx.start.line)
self.errors.append(error)
return type_enum.Error
value = var.stype
if ctx.expr:
if not var.listSize:
error = genericError(
'symbol of type %s is non suscriptable' % var.stype,
ctx.start.line)
self.errors.append(error)
return type_enum.Error
num_expr = ctx.expr.getText()
try:
num = int(num_expr)
if num < 0 or (num > var.listSize - 1):
error = genericError('Index out of range', ctx.start.line)
self.errors.append(error)
return type_enum.Error
except ValueError:
pass
visit = self.visit(ctx.expr)
if visit != type_enum.Integer:
error = genericError('Index must be an integer, got',
ctx.start.line)
self.errors.append(error)
return type_enum.Error
if ctx.loc:
struct = scope.typeExists(var.stype, type_enum.Struct)
if not struct:
error = genericError(
'Location passed but %s is not a struct' % var_name,
ctx.start.line)
self.errors.append(error)
return type_enum.Error
if ctx.loc.name.text not in struct.paramlist:
error = genericError(
'Location %s not defined in struct of %s of type %s' %
(ctx.loc.name.text, var_name, var.stype), ctx.start.line)
self.errors.append(error)
return type_enum.Error
value = struct.paramlist[ctx.loc.name.text].stype
return value