anchor.diff:              if couldparse then
                   if size < minVectorSize then
                       eprintfn "Given value for -vsize was too small, using the minimum: %i." minVectorSize
  -                    parseArgsRec xss {optionsSoFar with vectorSize = minVectorSize; changed = true}
  +                    exit 1
                   else
                       parseArgsRec xss {optionsSoFar with vectorSize = size; changed = true}
               else
                   eprintfn "Option -vsize was followed by an invalid value."
  -                parseArgsRec xs optionsSoFar
  +                exit 1
           | _ ->
               eprintfn "Option -vsize needs to be followed by a number."
  -            parseArgsRec xs optionsSoFar
  +            exit 1
       | x::xs ->
           eprintfn "Option \"%s\" is unrecognized." x
           parseArgsRec xs optionsSoFar
  
positive.code: 
          let benchmarks = 
              match ops.benchmarks with 
              | [] -> ["bench1"; "bench2"] 
              | xss -> xss
  
          let modes = 
  
negative.code:             | [] -> [ "auto"; "numeric"] 
              | xss -> xss
  
          let bench1 = List.contains "1" benchmarks 
          let bench2 = List.contains "2" benchmarks 
          let auto = List.contains "auto" modes
          let numeric = List.contains "numeric" modes
  
  