For convenience, std.string should provide toString overloads that accept char[], const(char)[], and Object. Currently, for generic template code, you have to do the following:

---
import std.string;
alias std.string.toString toString;
string toString(Object o) { return (o ? o.toString : "null"); }
string toString(string s) { return s; }

template (T) {
   T t;
   // ...
   toString(t);
}
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