[lnanek2]

He doesn't seem to know much about iOS or Objective-C due to that comment about parameter names probably being unused. You wouldn't be able to make meaningful method selectors calling into the code from Objective-C without them, since the names of the parameters are part of the method name in Objective-C.

[kennywinker]

Method parameter names are used similarly in Swift as in ObjC. For example two methods can have the same name, as long as they have a difference set of parameters. For example:

    func methodName(paramName: String)

and

    func methodName(paramName: String, otherParam: Int)

are different.

I'm still playing with this but there are some interesting/weird things in here. What follows is a bunch of random observations of how named params work in Swift / ObjC. For instance:

    func methodName(name name: String)

Can be shortened using a pound symbol, because the variable name within the method, and the parameter name are the same thing:

    func methodName(#name: String)

It also seems that most of the Cocoa APIs follow a convention, when called from Swift, of having an unnamed first parameter, and a named second parameter. e.g. this:

    -(UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath

becomes:

    func tableView(tableView: UITableView!, cellForRowAtIndexPath indexPath: NSIndexPath!) -> UITableViewCell!

which means it's called like so:

    myObject.tableView(tableView, cellForRowAtIndexPath: indexPath)

If you name a parameter, you have to use the name. The order of parameters matters, and there doesn't seem to be a way to define optional method parameters (make sense as parameter names are essentially ObjC "selectors").

[mercutio2]

> and there doesn't seem to be a way to define optional method parameters

Did you miss the part about default values?

If you're calling an Objective-C selector with more than one argument, you are indeed using an external parameter name, but external parameters are explicitly not required if you're writing pure Swift.

https://developer.apple.com/library/prerelease/ios/documenta...

[kennywinker]

Oh cool, I definitely missed that!