Call a parent toString that takes an optional argument.

[Tutez64]

HX_DEFINE_SCRIPTABLE always calls __superString::toString() with no arguments. A Haxe toString(indent = 0) is one C++ parameter, so that call does not compile.

The zero-argument form is used when it exists. Otherwise null is passed for the default.

The cppia host build compiles OptionalToString, whose toString takes an optional argument, and ZeroArgToString, whose toString does not. Without this change that host build does not compile.

[tobil4sk]

Seems like this is more of a specific hack to fix a program with that toString signature, but not a good general solution if the toString signature is different

[Tutez64]

You're right. Passing null only covered a single optional parameter. Looking closer, the failing case is a class that inherits a toString with parameters: that C++ overload hides hx::Object::toString(), and gencpp's __superString is then the class itself. Natively, Std.string on such an object reaches hx::Object::toString() whatever the signature, so in 95c73b3 the wrapper now falls back on exactly that when the parent has no zero-argument toString. The cppia tests now build host classes that inherit toString(indent = 0) and toString(indent, prefix), and check at run time that script subclasses print like native ones.