Discussion Thread: DIP 1030--Named Arguments--Final Review

[Jonathan Marler]

On Wednesday, 13 May 2020 at 19:31:24 UTC, Steven Schveighoffer 
wrote:
> On 5/13/20 3:30 PM, Walter Bright wrote:
>> On 5/13/2020 12:55 AM, Jacob Carlborg wrote:
>>> Regarding renaming parameters will break the API. Swift 
>>> supports giving a different name which are used locally:
>>>
>>> func copy(_ source: String, to destination: String)
>>>
>>> Should be called like this:
>>>
>>> copy("foo", to: "bar")
>>>
>>> `_` indicates that the argument can not be named when calling 
>>> the function.
>> 
>> In D, we do:
>> 
>>     void copy(string, string destination);
>
> And how does the implementation of copy use that first 
> parameter?
>
> -Steve

I found a way:

void copy(string, string destination)
{
     alias source = _param_0;
}

I didn't realize you could do this till now but this allows 
functions to "opt-out" of using named parameters.  We may want to 
consider using this pattern throughout phobos/druntime when we 
want want to prevent parameter names from being apart of the API.