Validations with MASK

Hi,
I must validate a field A4, that contains the hour in format Hour(2) Minute(2) HHMM. As MM is interpreted as Month, I used
IF NOT

In a MASK clause, an H represents a hexadecimal digit, not an hour; there is no character to represent a minute.

For the hour value, test for 0-23. For the minute value, test for 0-59.

DEFINE DATA LOCAL  
1 #A (A4)  INIT <'1230'>  
1 #T (T)  
1 #M (A25)  
END-DEFINE  
*  
REPEAT  
  INPUT #A (AD=MDLT)  
     // #T (AD=O ZP=F)  
     // #M (AD=O)  
  IF   #A = MASK (00-23)  
   AND #A = MASK (..00-59)  
    THEN  
      MOVE EDITED #A TO #T (EM=HHII)  
      RESET #M  
    ELSE  
    ASSIGN #M = 'invalid time value'  
    RESET #T  
  END-IF  
END-REPEAT  
END

http://techcommunity.softwareag.com/ecosystem/documentation/natural/nat424mf/pg/pg_furth_lcc.htm#Mask_Characters

You can also use

 IF #A = MASK (00-2300-59) ... 

Ralph/ Wilfried:
Thank you very much for your comments. Both them were pretty useful for me, included the link to the documentation.
Regards, Fabi