AV
let getOperands (expr:string) =
let mutable err = None
let res = ResizeArray<_>()
for e in expr.Split(' ') do
if err.IsNone then
let parsed = parseOperand e
match parsed with
| Ok op -> res.Add(op)
| Error e -> err <- Some e
if err.IsSome then
Result.Error err.Value
else
Result.Ok (res.ToArray())