Trivially convert from Preserve[void] to Preserve[E]

src/preserves.nim

@@ -31,6 +31,8 @@ proc hash*(s: Symbol): Hash {.borrow.}
 
 type
   Preserve*[E = void] = object
+    embedded*: bool
+      ## Flag to mark embedded Preserves
     case kind*: PreserveKind
     of pkBoolean:
       bool*: bool
@@ -58,8 +60,6 @@ type
         # TODO: Tables
     of pkEmbedded:
       embed*: E
-    embedded*: bool
-      ## Flag to mark embedded Preserves
 
   DictEntry[E] = tuple[key: Preserve[E], val: Preserve[E]]
 
@@ -749,6 +749,8 @@ proc toPreserve*[T](x: T; E = void): Preserve[E] =
   elif T is E:
     when E is void: {.error: "cannot embed void".}
     result = embed(x)
+  elif T is Preserve[void]:
+    result = cast[Preserve[E]](x)
   elif compiles(toPreserveHook(x, E)):
     result = toPreserveHook(x, E)
   elif T is enum: