Parse tree for http://pastebin.com/TTbCKshW

(infix CR
 (infix ->
  (infix else
   (infix then
    (prefix
     // If-then-else statement
     if
     true)
    TrueBody)
   FalseBody)
  (prefix
   do
   TrueBody
  ))
 (infix CR
  (infix ->
   (infix else
    (infix then
     (prefix
      if
      false)
     TrueBody)
    FalseBody)
   (prefix
    do
    FalseBody

   ))
  (infix CR
   (infix ->
    (infix then
     (prefix
      if
      true)
     TrueBody)
    (prefix
     do
     TrueBody
    ))
   (infix CR
    (infix ->
     (infix then
      (prefix
       if
       false)
      TrueBody)
     false

    )
    (infix CR
     (prefix
      // Building lists, notably lists of arguments
      data
      (infix ,
       x
       y

      ))
     (infix CR
      (infix ->
       (prefix
        // Console / debugging operations
        write
        (infix ,
         x
         y))
       (infix ;
        (prefix
         write
         x)
        (prefix
         write
         y
        )))
      (infix CR
       (infix ->
        (prefix
         writeln
         x)
        (infix ;
         (prefix
          write
          x)
         writeln

        ))
       (infix CR
        (infix ->
         (prefix
          // Min and max functions
          min
          (infix ,
           x
           y))
         (infix else
          (infix then
           (prefix
            if
            (infix <
             x
             (prefix
              min
              y)))
           x)
          (prefix
           min
           y
          )))
        (infix CR
         (infix ->
          (prefix
           min
           y)
          y
         )
         (infix CR
          (infix ->
           (prefix
            max
            (infix ,
             x
             y))
           (infix else
            (infix then
             (prefix
              if
              (infix >
               x
               (prefix
                max
                y)))
             x)
            (prefix
             max
             y
            )))
          (infix CR
           (infix ->
            (prefix
             max
             y)
            y

           )
           (infix CR
            (infix ->
             (infix in
              (infix :
               // Interval test
               X
               real)
              (infix ..
               (infix :
                A
                real)
               (infix :
                B
                real)))
             (infix and
              (infix >=
               X
               A)
              (infix <=
               X
               B

              )))
            (infix CR
             (infix ->
              (postfix
               // Factorial function
               0
               !)
              1
             )
             (infix CR
              (infix ->
               (infix :
                N
                (postfix
                 integer
                 !))
               (infix *
                N
                (postfix
                 (block ( )
                  (infix -
                   N
                   1))
                 !)

               ))
              (infix CR
               (infix ->
                (prefix
                 // Boolean to text conversion
                 text
                 true)
                "true"
               )
               (infix ->
                (prefix
                 text
                 false)
                "false"
               ))))))))))))))))
(infix CR
 (infix ->
  (prefix
   // A custom notation to repeat a shape
   (block [ ]
    (infix ..
     A
     B))
   Body)
  (block  indent
   (infix loop
    (prefix
     for
     (infix in
      I
      (infix ..
       A
       B)))
    (block  indent
     (prefix
      locally
      (block  indent
       (infix CR
        (prefix
         color_hsv
         (infix ,
          (infix *
           20
           I)
          (infix ,
           (postfix
            90
            %)
           (infix ,
            (postfix
             70
             %)
            (postfix
             40
             %)
           ))))
        (infix CR
         (prefix
          rotate_z
          (infix *
           17
           I
          ))
         Body

        ))))))))
 (infix CR
  (prefix
   // Tao3D can use indentation-based blocks
   (block [ ]
    (infix ..
     1
     5))
   (block  indent
    (infix CR
     (prefix
      ellipse
      (infix ,
       100
       (infix ,
        0
        (infix ,
         140
         30
        ))))
     (infix CR
      (prefix
       translate_x
       (prefix
        -
        180
       ))
      (infix CR
       (prefix
        font
        (infix ,
         "Arial"
         40
        ))
       (prefix
        text
        "Hello"

       ))))))
  (prefix
   // Or {} blocks if you prefer...
   (block [ ]
    (infix ..
     3
     20))
   (block { }
    (prefix
     rectangle
     (infix ,
      50
      (infix ,
       20
       (infix ,
        30
        25)))))
  )))