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discard """
nimout: "tcheckedfield1.nim(39, 6) Warning: cannot prove that field 'x.s' is accessible [ProveField]"
action: run
output: "abc abc"
"""
import strutils
{.warning[ProveField]: on.}
{.experimental: "notnil".}
type
TNodeKind = enum
nkBinary, nkTernary, nkStr
PNode = ref TNode not nil
TNode = object
case k: TNodeKind
of nkBinary, nkTernary: a, b: PNode
of nkStr: s: string
PList = ref object
data: string
next: PList
proc getData(x: PList not nil) =
echo x.data
var head: PList
proc processList() =
var it = head
while it != nil:
getData(it)
it = it.next
proc toString2(x: PNode): string =
if x.k < nkStr:
toString2(x.a) & " " & toString2(x.b)
else:
x.s
proc toString(x: PNode): string =
case x.k
of nkTernary, nkBinary:
toString(x.a) & " " & toString(x.b)
of nkStr:
x.s
proc toString3(x: PNode): string =
if x.k <= nkBinary:
toString3(x.a) & " " & toString3(x.b)
else:
x.s # x.k in {nkStr} --> fact: not (x.k <= nkBinary)
proc p() =
var x: PNode = PNode(k: nkStr, s: "abc")
let y = x
if not y.isNil:
echo toString(y), " ", toString2(y)
p()
|
