B.3.3 Valid_State_Integer Procedure

The main documentation of the Valid_State_Integer Procedure contains additional explanation of this code listing.

  define([REPLICATE_ROUTINE],[
    ifelse(POINTER_TOGGLE, [TRUE], [
      pushdef([TYPE], [integer,$1])
      pushdef([Valid_State_Integer_P_DIM], expand(Valid_State_Integer_P_$1))
      pushdef([POINTER_ONLY], [])
    ],[
      pushdef([TYPE], [integer,$1,np])
      pushdef([Valid_State_Integer_P_DIM], expand(Valid_State_Integer_NP_$1))
      pushdef([POINTER_ONLY], [!])
    ])
    
    function Valid_State_Integer_P_DIM (I) result(Valid)
  
      ! Use association information.
  
      SCALAR_ONLY use Caesar_Flags_Module, only: finalize_integer_flag 
      SCALAR_ONLY use Caesar_Logical_Class, only: ALL
  
      ! Input variable.
      
      type(TYPE) :: I  ! Variable to be checked.
  
      ! Output variable.

      type(logical) :: Valid      ! Logical state.
  
      !~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  
      ! Start out true.
  
      Valid = .true.
  
      ! First, make sure that the variable has been allocated.
  
      POINTER_ONLY ARRAY_ONLY Valid = Valid .and. ASSOCIATED(I)
      POINTER_ONLY ARRAY_ONLY if (.not.Valid) return

      ! Make sure the variable has not been finalized.
      
      SCALAR_ONLY Valid = Valid .and. I /= finalize_integer_flag
      
      ! Check the top of the range.
      
      Valid = Valid .and. ALL(I <= HUGE(I)) 
      
      ! Note that there is no explicit check for the bottom of the
      ! range, since there is no F90 intrinsic that returns the lowest
      ! negative number that an integer can take.
  
      return
    end function Valid_State_Integer_P_DIM

    popdef([TYPE])
    popdef([Valid_State_Integer_P_DIM])
    popdef([POINTER_ONLY])
  ])

  define([POINTER_TOGGLE], [TRUE])
  REPLICATE

  define([POINTER_TOGGLE], [FALSE])
  REPLICATE