I keep on trying to understand what goes on with the move semantics.
I am trying the following:
import vs
proc main =
let c1 = source("2sec.mkv") # OK
discard c1.saveY4M("demo.y4m") # OK
echo c1 # OK
`=destroy`(c1) # shows 'destroying VSMapObj'
echo c1.handle.isNil # shows 'false'
# shows 'destroying VSMapObj' again
main()
Run
It saves the video file and echos `c1`.
Then I try to manually destroy `c1`.
Bearing in mind that:
type
VSMapObj* = object
handle*:ptr VSMap
proc `=destroy`*(self: VSMapObj) =
if not self.handle.isNil:
echo "destroying VSMapObj"
api.handle.freeMap(self.handle)
Run
The output is:
destroying VSMapObj
VSMap: 1 item(s)
(key: "clip", typ: ptvideonode, n: 1, idx: 0)
destroying VSMapObj
false
destroying VSMapObj
Traceback (most recent call last)
/home/jose/src/nimlang/vs.nim/tests/ex08_mm1.nim(11) ex08_mm1
/home/jose/src/nimlang/vs.nim/src/lib/libvsmap.nim(31) main
/home/jose/src/nimlang/vs.nim/src/lib/libvsmap.nim(34) =destroy
SIGSEGV: Illegal storage access. (Attempt to read from nil?)
Error: execution of an external program failed:
'/home/jose/src/nimlang/vs.nim/tests/ex08_mm1'
Run
I would expect `c1.handle.isNil` being `nil`, wouldn't it?
The generated code is:
var
c1
:tmpD
:tmpD_1
:tmpD_2
:tmpD_3
:tmpD_4
try:
c1 = source("2sec.mkv", none(int), none(int),
:tmpD = none_1(string)
:tmpD, none(int), none(int), none(int),
:tmpD_1 = none_1(string)
:tmpD_1, none(int), none(int), none(int),
:tmpD_2 = none_1(string)
:tmpD_2, none(int), none(int))
discard saveY4M(c1, "demo.y4m")
echo [
:tmpD_3 = `$`(c1)
:tmpD_3]
`=destroy`(c1)
echo [
:tmpD_4 = `$`(isNil(c1.handle))
:tmpD_4]
finally:
`=destroy`(:tmpD_4)
`=destroy`(:tmpD_3)
`=destroy_2`(:tmpD_2)
`=destroy_2`(:tmpD_1)
`=destroy_2`(:tmpD)
`=destroy`(c1)
Run
