nimforum mirror - Any workarounds for view-object bugs?

snej (orginal) [2020-11-09T20:23:22+01:00] view original

I'm trying to use view objects in 1.4 and devel. Even my simplest test cases are either crashing, returning bogus values, or triggering C compile errors. For example:

type Outer = object
  value: int
type Inner = object
  owner: var Outer

var o = Outer(value: 1234)
var v = Inner(owner: o).owner.value
echo "Got value = ", v
assert v == 1234

This fails with a C compile error.

If you change Outer to ref object, it crashes.

If you change Outer to ref object of RootObj, it gets a bogus value for v (8) and fails the assertion.

I just filed issue 15897 on this, and the issues 15884 and 15885 filed yesterday look very similar.

I have a good use case for a view object; does anyone know of a way to avoid these issues?

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7061 :: Any workarounds for view-object bugs?