Shorthand constructor this.x parameters prohibit access to x in initializer list

[sethladd]

This may be a known trade-off, but I was curious if this was a bug.

I tried to do:

class Point {
  final num x;
  final num y;
  final num distanceFromOrigin;
  
  Point(this.x, this.y) : distanceFromOrigin = calcDistance(x, y);
  
  static calcDistance(_x, _y) => Math.sqrt((_x*_x) + (_y*_y));
}

But the Editor (rightly so?) said "cannot access field in initializer expression". I understand 'this' isn't available in initializer lists, but I was a little surprised that I couldn't access the implicit x from the constructor parameter.

I ended up writing:

class Point {
  final num x;
  final num y;
  final num distanceFromOrigin;
  
  Point(x, y) :
    x = x,
    y = y,
    distanceFromOrigin = calcDistance(x, y);
  
  static calcDistance(_x, _y) => Math.sqrt((_x*_x) + (_y*_y));
}

Sounds like the tradeoff is "use the shorthand constructor parameter names or initializer lists"

[gbracha]

This is a known trade off. If you need to use the incoming parameters for more than just setting the corresponding fields, you can do so in the constructor body, but not in the initializer list.

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Removed Type-Defect label.
Added Type-Enhancement, WontFix labels.

[gbracha]

Issue #4181 has been merged into this issue.