SwiftIssues.md

Issues with Swift

Below a collection of issues I've found in the current implementation of Swift. Presumably they fix most of them pretty quickly.

FIXME: Collect and list all issues :-)

Bugs

• Hang on long constant strings
• No access to ioctl()
• sizeof() only works on types, not on variables/constants (No var buf: CInt; sizeof(buf) - lame! ;-)
  • TBD: sizeofValue()?
• Cannot put methods into extensions which are going to be overridden ('declarations in extensions cannot be overridden yet')
• no let constant = 42 in extensions, gives "'var' declarations without getter/setter not allowed here" (this ain't no var)

How To?

Error Handling

I'm not sure how we are supposed to handle errors in Swift. Maybe using some enum for the error codes and a fallback value (e.g. the file descriptor) for the success case. Kinda like an Optional, with more fail values than nil.

Casting C Structures

FIXME: this is a bit different now, maybe it works just fine.

How should we cast between typed pointers? Eg bind() takes a &sockaddr, but the actual structure is variable (eg a sockaddr_in).

I hacked around it like this:

var addr = address // where address is sockaddr_in
    
// CAST: Hope this works, essentially cast to void and then take the rawptr
let bvptr: CConstVoidPointer = &addr
let bptr = CConstPointer<sockaddr>(nil, bvptr.value)

Which doesn't feel right.

Flexible Length C Structures

I guess this can be done with UnsafePointer. Structures like sockaddr_un, which embed the path within the structure and thereby have a different size.

Overloading functions with Optionals

This seems to behave a bit weird (forgot the details ;-):

func getSocketOption(option: CInt) -> CInt {
  return 0
}
func getSocketOption(option: CInt?) -> CInt {
  return 0
}