Null Coalescing Operator kills the compiler?

Question

Created Oct ’16

Replies 3

Boosts 0

Participants 3

We have been migrating our App from Swift 2 to 3 and with all the bug fixing etc we noticed the compiler was hanging and never finishing. After a great deal of time pull in the project apart to narrow down the problem we have found that Null Coalescing Operator when used in certain situations will cause the compiler to hang...

This will cause the compiler to hang

let values = "\(customer.name),"
            + "\(customer.telephone),"
            + "\(customer.email),"
            + "\(customer.deliveryAddress1),"
            + "\(customer.deliveryTown),"
            + "\(customer.deliveryPostcode ?? ""),"
            + "\(customer.deliveryCountryCode)"

where as this will not

let values = "\(customer.name),"
            + "\(customer.telephone),"
            + "\(customer.email),
            + "\(customer.deliveryAddress1),"
            + "\(customer.deliveryTown),"
            + "\(customer.deliveryPostcode != nil ? customer.deliveryPostcode : ""),"
            + "\(customer.deliveryCountryCode)"

I hope this will cause the compiler team to take a look and hopefully fix this issue.

Boost

Answer 1

Chrispem OP

Oct ’16

It also seems to struggle with type inference...

Sooooo slow...

if let newCustomer: NewCustomer = find(customerID: customerID) {
            let parameters : [String : Any] = [
                "Name": newCustomer.name,
              
                "RegNo": newCustomer.regNo,
                "VatNo": newCustomer.vatNo ?? "",
              
                "Telephone": newCustomer.telephone,
                "Email": newCustomer.email,
                "Website": newCustomer.website ?? "",
              
                "ContactName": newCustomer.contactName,
                "ContactPosition": newCustomer.contactPosition,
                "ContactTelephone": newCustomer.contactTelephone,
              
                "InvoiceAddress1": newCustomer.invoiceAddress1,
                "InvoiceAddress2": newCustomer.invoiceAddress2 ?? "",
                "InvoiceAddress3": newCustomer.invoiceAddress3 ?? "",
                "InvoiceTown": newCustomer.invoiceTown,
                "InvoiceCounty": newCustomer.invoiceCounty ?? "",
                "InvoicePostcode": newCustomer.invoicePostcode ?? "",
                "InvoiceCountryCode": newCustomer.invoiceCountryCode,
              
                "DeliveryAddress1": newCustomer.deliveryAddress1,
                "DeliveryAddress2": newCustomer.deliveryAddress2 ?? "",
                "DeliveryAddress3": newCustomer.deliveryAddress3 ?? "",
                "DeliveryTown": newCustomer.deliveryTown,
                "DeliveryCounty": newCustomer.deliveryCounty ?? "",
                "DeliveryPostcode": newCustomer.deliveryPostcode ?? "",
                "DeliveryCountryCode": newCustomer.deliveryCountryCode,
  
                "SalesmanAreaCode": newCustomer.salesmanAreaCode,
                "PriceCategoryID": newCustomer.priceCategoryID,
                "DiscountPercentage": newCustomer.discountPercentage,
                "PaymentTermsID": newCustomer.paymentTermsID
            ]
}

Instant...

if let newCustomer: NewCustomer = find(customerID: customerID) {
            let parameters : [String : Any] = [
                "Name": newCustomer.name as String,
               
                "RegNo": newCustomer.regNo as String,
                "VatNo": newCustomer.vatNo ?? "" as String,
               
                "Telephone": newCustomer.telephone as String,
                "Email": newCustomer.email  as String,
                "Website": newCustomer.website ?? "" as String,
               
                "ContactName": newCustomer.contactName as String,
                "ContactPosition": newCustomer.contactPosition as String,
                "ContactTelephone": newCustomer.contactTelephone as String,
               
                "InvoiceAddress1": newCustomer.invoiceAddress1 as String,
                "InvoiceAddress2": newCustomer.invoiceAddress2 ?? "" as String,
                "InvoiceAddress3": newCustomer.invoiceAddress3 ?? "" as String,
                "InvoiceTown": newCustomer.invoiceTown as String,
                "InvoiceCounty": newCustomer.invoiceCounty ?? "" as String,
                "InvoicePostcode": newCustomer.invoicePostcode ?? "" as String,
                "InvoiceCountryCode": newCustomer.invoiceCountryCode as String,
               
                "DeliveryAddress1": newCustomer.deliveryAddress1 as String,
                "DeliveryAddress2": newCustomer.deliveryAddress2 ?? "" as String,
                "DeliveryAddress3": newCustomer.deliveryAddress3 ?? "" as String,
                "DeliveryTown": newCustomer.deliveryTown as String,
                "DeliveryCounty": newCustomer.deliveryCounty ?? "" as String,
                "DeliveryPostcode": newCustomer.deliveryPostcode ?? "" as String,
                "DeliveryCountryCode": newCustomer.deliveryCountryCode as String,
   
                "SalesmanAreaCode": newCustomer.salesmanAreaCode as String,
                "PriceCategoryID": newCustomer.priceCategoryID as Int,
                "DiscountPercentage": newCustomer.discountPercentage as Double,
                "PaymentTermsID": newCustomer.paymentTermsID as Int
            ]
}

0

Answer 2

jlilest002 OP

Oct ’16

You should file a bug report using the report bug link at the bottom of the page.

These groups aren't monitored for bug reports.

0

Answer 3

Claude31 OP

Oct ’16

I suppose deliveryPostCode is an optional in your code ?

Then the line should unwrap :

+ "\(customer.deliveryPostcode != nil ? customer.deliveryPostcode! : ""),"

0