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|
discard """
output: '''5
vseq destroy
'''
joinable: false
"""
type
opt*[T] = object
case exists: bool
of true: val: T
of false: discard
proc some*[T](val: sink T): opt[T] {.inline.} =
## Returns an ``opt`` that has the value.
## nil is considered as none for reference types
result = opt[T](exists: true, val: val)
proc none*(T: typedesc): opt[T] {.inline.} =
## Returns an ``opt`` for this type that has no value.
# the default is the none type
discard
proc none*[T]: opt[T] {.inline.} =
## Alias for ``none(T)``.
none(T)
proc unsafeGet*[T](self: opt[T]): lent T {.inline.} =
## Returns the value of a ``some``. Behavior is undefined for ``none``.
self.val
type
VSeq*[T] = object
len: int
data: ptr UncheckedArray[T]
proc `=destroy`*[T](m: var VSeq[T]) {.inline.} =
if m.data != nil:
echo "vseq destroy"
dealloc(m.data)
m.data = nil
proc `=`*[T](m: var VSeq[T], m2: VSeq[T]) {.error.}
proc `=sink`*[T](m: var VSeq[T], m2: VSeq[T]) {.inline.} =
if m.data != m2.data:
`=destroy`(m)
m.len = m2.len
m.data = m2.data
proc newVSeq*[T](len: int): VSeq[T] =
## Only support sequence creation from scalar size because creation from
## vetorized size can't reproduce the original scalar size
result.len = len
if len > 0:
result.data = cast[ptr UncheckedArray[T]](alloc(sizeof(T) * len))
let x = some newVSeq[float](5)
echo x.unsafeGet.len
let y = none(VSeq[float])
|
