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120 :: Immutable object

[2013-01-21T07:02:25+01:00]

exhu (orginal) [2013-01-21T07:02:25+01:00] view original
how to declare an object, which cannot be modified after creation/initialization? e.g. I want the user not be able to modify fields a and b after the object has been initialized:
```
TMyObject = object
  a* : proc
  b* : proc

proc initMyObject(o: var TMyObject) =
  a = someproc
  b = someproc
```

Araq (orginal) [2013-01-21T09:07:27+01:00] view original

Provide accessor procs for 'a' and 'b' then and don't export them directly. However, I'm considering to add readonly fields to the language as they seem so simple to implement ...

exhu (orginal) [2013-01-21T12:11:02+01:00] view original

BTW, any plans for const/immutable stuff the D-way? :)

Araq (orginal) [2013-01-21T13:06:25+01:00] view original

No. We already have shallow immutability via let and the parameter passing semantics. Deep immutability is planned to be provided via Nimrod's effect system; however immutability does not buy you much when you have thread-local heaps anyway.