anchor.diff:  let ``First row contains 'A'`` (letter : char) =
       let actual = make letter
       let rows = split actual
  -
  -    // Note: 
  -    // - A string is a sequence (`Seq`) of characters
  -    // - The 1st entry in a sequence is `Seq.head`
       rows |> Seq.head |> trim = "A"
   
   let leadingSpaces (x : string) =
  
positive.code: [<DiamondProperty>]
  let ``All rows must have a symmetric contour`` (letter : char) =
      let actual = make letter
  
      let rows = split actual
      rows |> Array.forall (fun r -> (leadingSpaces r) = (trailingSpaces r))
  
  [<DiamondProperty>]
  let ``Top of figure has correct letters in correct order`` (letter : char) =
      let actual = make letter
      printfn "%s" actual
  
      let expected = ['A' .. letter]
      let rows = split actual
      
  
negative.code: 
  [<DiamondProperty>]
  let ``Dimaond is non empty`` (letter : char) =
      let actual = make letter
      not (String.IsNullOrWhiteSpace actual)
  
  