[feature request] Default value for enum parameters

[sebthom]

I was surprised to find that while

enum Schedule {
    Hourly(?minute:Int);
    // ...
}

is possible, this is not:

enum Schedule {
    Hourly(minute:Int=1); // characters 18-19 : Unexpected =
    // ...
}

Right now I have to do additional null-checks on enums with optional parameters like so

var instance = new MyClass(Schedule.Hourly());

function MyClass {
    var schedule:Schedule;

    public function new(var schedule:Schedule){
       // validate schedule
       switch (schedule) {
           case Hourly(minute):
                // check for null and apply a default value if found
                if(minute == null) {
                   minute = 1;
                   schedule = Schedule.Hourly(minute); 
                } else if (minute < 0 || minute > 59)  
                   throw "Hourly.Minute must be >= 0 and < 60";
                }
            // ...
       }
       this.schedule = schedule;
    }
}

instead of simply:

var instance = new MyClass(Schedule.Hourly());

function MyClass {
    var schedule:Schedule;

    public function new(var schedule:Schedule) {
       // validate schedule
       switch (schedule) {
           case Hourly(minute):
                if (minute < 0 || minute > 59)  
                    throw "Hourly.Minute must be >= 0 and < 60";
            // ...
       }
       this.schedule = schedule;
    }
}

Therefore I would request adding default value behaviour for enums as specified here https://haxe.org/manual/types-function-default-values.html

[Simn]

This would have to go through https://github.com/HaxeFoundation/haxe-evolution.

[sebthom]

HaxeFoundation/haxe-evolution#27