Implicit cast for overloaded record in Delphi as a parameter in a const array

Question

We got rid of shortstring as part of a conversion from Delphi 7. I wanted to make it as painless as possible so we figured we could change the ShortString to some record which acted in the same way. Here's how it's declared (there's more to it, but this is the basic structure, which outlines the problem):

TShortStringRec = record 
private
  FStuff: array [0..49] of Char;
public
  class operator Implicit(AStuff: TShortStringRec): String;
  class operator Implicit(S1: String): TShortStringRec;
end;

This works well for setting strings to the record. But then there's functions like format which take as its parameter const array of const's. Is there any way to do an implict cast to what we'd want to pass into a const array?

function FunkyFunc : string;
var
  ssr : TShortStringRec;
begin
  ssr := 'Wall'; 
  result := format('Hello %s', [ssr]);  //<---error here
end;

Gives a syntax error while compiling because ssr is not a type of parameter that you can use on one of those arrays.

Answer 1

Short answer: No.
Long answer: What you're asking for is that the compiler to somehow know that you want a inherently untyped parameter to be coerced into the type you intend. The compiler simply doesn't have enough information at the call-site to make the determination. If you add an "Explicit" operator and then explicitly cast the parameter to a string, then it will work.