I can rewrite it this way:
O {.bycopy.} = object
i: int
proc new(o: var O) =
echo "new called"
proc `=destroy`*(s: var O) =
echo "=destroy called"
proc `=sink`*(a: var O; b: O) =
echo "=sink called"
a.i = b.i
proc createO: O =
result.i = 7
proc p(o: sink O) =
echo "working with o"
echo o.i
proc main =
var
o: O = createO()
p(o)
echo o.i
main()
nim
Run
$ ./h
=sink called
working with o
7
7
=destroy called
Run
So p() has a sink parameter. But should not the echo after call of p() force a
copy, so that we get two destroys?
