XL: An Extensible Programming Language(xlr.sourceforge.io)

  ./xl -nobuiltins -parse /tmp/glop.xl -style debug -show
  (infix is
   is
   is
  )

  // If-then-else statement
  if [[true]]  then True else False   is True
  if [[false]] then True else False   is False

  if [[true]]  then True              is True
  if [[false]] then True              is false

  // Loops
  while Condition loop Body is
      if Condition then
          Body
          while Condition loop Body
  until Condition loop Body               is { while not   Condition loop Body }
  loop Body                               is { Body; loop Body }
  for Var in Low..High loop Body is
      Var := Low
      while Var < High loop
          Body
          Var := Var + 1