string literal string and immutable(char)* overload ambiguity

[Steven Schveighoffer]

On 8/3/18 10:26 AM, Jonathan Marler wrote:
> On Tuesday, 31 July 2018 at 15:07:04 UTC, Steven Schveighoffer wrote:
>> On 7/31/18 10:13 AM, Nicholas Wilson wrote:
>>> is there any particular reason why
>>>
>>> void foo(string a) {}
>>> void foo(immutable(char)* b) {}
>>>
>>> void bar()
>>> {
>>>      foo("baz");
>>> }
>>>
>>> result in
>>>
>>> Error: foo called with argument types (string) matches both:
>>> foo(string a)
>>> and:
>>> foo(immutable(char)* b)
>>>
>>> especially given the pointer overload is almost always
>>> void foo(immutable(char)* b)
>>> {
>>>      foo(b[0 .. strlen(b)]);
>>> }
>>> and if I really want to call the pointer variant I can with
>>>      foo("baz".ptr);
>>> but I can't call the string overload with a literal without creating 
>>> a temp.
>>>
>>> I think we should make string literals prefer string arguments.
>>>
>>
>> Absolutely, I didn't realize this was an ambiguity. It should be the 
>> same as foo(long) vs. foo(int) with foo(1).
>>
> 
> +1 for this
> 
> Although there is a solution for this today, i.e.
> 
> foo(cast(string)"baz");
> foo("baz".ptr));
> 
> I see no reason why `string` shouldn't have precedence over 
> `immutable(char)*`, especially since you can always explicitly choose 
> the pointer variant with `.ptr.
> 
Let me rewrite your solution for int vs. long:

foo(cast(int)1);
foo(1L);

You like that too? ;)

"baz" is a string, that's its primary type. That it can be used for a 
const(char)* is nice for legacy C code, but shouldn't get in the way of 
its natural type.

-Steve