View source for Free Form Calcs

[[Category:RPG]]
[[Category:Programming]]
One of the major new features of RPG 4, introduced in [[V5R1]], is free form calculation specifications.
=Features=
* Removes the column restrictions on calculations.
* Can be interspersed with standard, fixed form, calcs
=Usage=
Using free form calculations is quite easy.

* To start a section of free form calculations, simply put '/free' starting in column 7.
* On the next line start your free form calculations.
* Each line must end with a semi-colon ";".
* Calculations can span multiple lines.
* End the free form calculation area by putting '/end-free' starting in column 7 on the last line.
=Limitations=
certain opcodes have not been implemented in free form RPG.  Many have been replaced with corresponding [[RPG Built In Functions | built in functions]].

These include ...
* Move operations (it is debatable as to the wisdom of not supporting these operations)
** MOVE
** MOVEL
** MOVEA
** MHHZO 
** MHLZO 
** MLHZO 
** MLLZO 
* Arithmetic operations (use free form evaluations or corresponding built in function)
** ADD
** SUB
** DIV
** MULT
** MVR
** XFOOT (use [[%XFOOT]])
* Comparison (use free form comparisons)
** COMP
** IFxx
** WHENxx
* Flow control
** DO
** GOTO
* Parameters (use [[prototyped calls]])
** PARM
** PLIST
* Other
** TESTB
** TESTN
** TESTZ
** XLATE (use [[%XLATE]])

=Example=
<source lang="rpg">
C                   if        PCFRS = '*ALL'                
C                   eval      #CFRSF = *BLANK               
C                   eval      #CFRSH = *BLANK               
C                   else                                    
C                   eval      #CFRSF = i_CF_Const(PCFRS)    
C                   eval      #CFRSH = #CFRSF               
C                   endif                                   
                                                            
 /free                                                      
  if (pMOLS = '*ALL');                                      
    eval #MOLSF = *blank;                                   
    eval #MOLSH = *blank;                                   
  else;                                                     
    eval #MOLSF = pMOLS;                                    
    eval #MOLSH = pMOLS;                                    
  endif;                                                    
 /end-free                                             
     
C     C#RTNS        IFNE      '*EXITPGM'               
C     C#RTNS        ANDNE     '*RETURN'                                                                            
</source >