progress-4gl Functions Multiple return statements (but a single return value)
Example
A function can have multiple return statements and they can be placed in different parts of the actual function. They all need to return the same data type though.
FUNCTION returning DATE ( dat AS DATE):
IF dat < TODAY THEN DO:
DISPLAY "<".
RETURN dat - 200.
END.
ELSE DO:
DISPLAY ">".
RETURN TODAY.
END.
END.
MESSAGE returning(TODAY + RANDOM(-50, 50)) VIEW-AS ALERT-BOX.
A function actually don't have to return anything at all. Then it's return value will be ? (unknown). The compiler will not catch this (but your colleagues will so avoid it).
/* This function will only return TRUE or ?, never FALSE, so it might lead to troubles */
FUNCTION inTheFuture LOGICAL ( dat AS DATE):
IF dat > TODAY THEN DO:
RETURN TRUE.
END.
END.
MESSAGE inTheFuture(TODAY + RANDOM(-50, 50)) VIEW-AS ALERT-BOX.
