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178 :: I dont understand distinct

[2013-07-03T19:59:19+02:00]

ventor3000 (orginal) [2013-07-03T19:59:19+02:00] view original
```
type TPoint=distinct tuple[x,y:float]
var pt:TPoint
pt.x=10.0
```
Generates an Error: undeclared field: 'x' on line 3 , this does not happen if TPoint is not distinct., why is that?

gradha (orginal) [2013-07-03T20:40:49+02:00] view original
Looks problematic. The following code works for me:
```
type
  APoint = tuple[x, y: float]
  TPoint= distinct APoint
var pt:APoint
pt = (10.0, 10.0)
```
Then, when I change the type of pt to TPoint it stops compiling with:
```
dist.nim(5, 6) Error: type mismatch: got (tuple[float, float]) but expected 'TPoint'
```
Writing pt = TPoint(10.0, 10.0) doesn't help either.

Araq (orginal) [2013-07-03T21:25:34+02:00] view original

'distinct' hides all the implementation aspects of the type, field access being the most prominent/annoying example. distinct with '.' is a planned feature though. That said, your example doesn't make much sense: If you want nominal typing for your TPoint just use an object.