https://issues.dlang.org/show_bug.cgi?id=23948

          Issue ID: 23948
           Summary: __FILE__ and __MODULE__ cannot be implicitly converted
                    to const(char)* as default paramenter
           Product: D
           Version: D2
          Hardware: x86_64
                OS: Linux
            Status: NEW
          Severity: enhancement
          Priority: P1
         Component: dmd
          Assignee: nobody@puremagic.com
          Reporter: mail@ernestocastellotti.it

One expects this code to be valid:

void foo(const(char)* mod = __MODULE__)() {

}

void main() {
    foo();
}


However you get the error:

onlineapp.d(9): Error: cannot implicitly convert expression `"onlineapp.d"` of
type `string` to `const(char)*`
onlineapp.d(9): Error: template instance `foo!((__error))` incompatible
arguments for template instantiation
onlineapp.d(9): Error: none of the overloads of template `onlineapp.foo` are
callable using argument types `!()()`
onlineapp.d(3):        Candidate is: `foo(const(char)* mod = __FILE__)

While if you do the same with __FUNCTION__ the code compiles:

void foo(const(char)* fun = __FUNCTION__)() {

}

void main() {
    foo();
}

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