DYNAMIC-FUNCTION function

Invokes a user-defined function. The AVM evaluates the name of the function (and the procedure handle, if any) at run time.


DYNAMIC-FUNCTION ( `function-name` [ IN `proc-handle` ] [ , `param1` [ , `param2` ] ... ] )

Parameters of the user-defined function. You must supply names of actual data items—actual parameter names—not CHARACTER expressions that return parameter names.

Note: ABL cannot check the mode and type of the parameters at compile time, since the AVM does not evaluate function-name until run time.

r-funfun.p
/* Requires a connection to the Sports2000 database. Define data items / DEFINE VARIABLE funcs AS CHARACTER NO-UNDO EXTENT 5 INITIAL ["firstrec","lastrec","nextrec","prevrec","quitting"]. DEFINE VARIABLE action AS CHARACTER NO-UNDO LABEL "Action" FORMAT "x" INITIAL "N". DEFINE VARIABLE idx AS INTEGER NO-UNDO. DEFINE VARIABLE alldone AS LOGICAL NO-UNDO. FORM WITH FRAME x SIDE-LABELS 2 COLUMNS 1 DOWN COLUMN 25. / Define user-defined functions / FUNCTION dispcust RETURNS LOGICAL: DISPLAY Customer EXCEPT Customer.Comments WITH FRAME x. END. FUNCTION firstrec RETURNS LOGICAL: FIND FIRST Customer. dispcust(). RETURN yes. END. FUNCTION lastrec RETURNS LOGICAL: FIND LAST Customer. dispcust(). RETURN yes. END. FUNCTION nextrec RETURNS LOGICAL: FIND NEXT Customer NO-ERROR. IF AVAILABLE Customer THEN dispcust(). RETURN AVAILABLE(Customer). END. FUNCTION prevrec RETURNS LOGICAL: FIND PREV Customer NO-ERROR. IF AVAILABLE Customer THEN dispcust(). RETURN AVAILABLE(Customer). END. FUNCTION quitting RETURNS LOGICAL: alldone = yes. RETURN no. END / Main routine */ REPEAT WHILE NOT alldone: UPDATE action HELP "Enter F(irst), L(ast), N(ext), P(rior), or Q(uit) to navigate.". idx = LOOKUP(action,"f,l,n,p,q"). IF idx EQ 0 THEN DO: MESSAGE "Enter F(irst), L(ast), N(ext), P(rior), or Q(uit)" VIEW-AS ALERT-BOX. NEXT. END. DISPLAY DYNAMIC-FUNCTION(funcs[idx]) LABEL "Record Found?". END.

r-funfun.p

/* Requires a connection to the Sports2000 database. Define data items */ 
DEFINE VARIABLE funcs   AS CHARACTER NO-UNDO EXTENT 5  
  INITIAL ["firstrec","lastrec","nextrec","prevrec","quitting"]. 
DEFINE VARIABLE action  AS CHARACTER NO-UNDO LABEL "Action" FORMAT "x"  
  INITIAL "N". 
DEFINE VARIABLE idx     AS INTEGER   NO-UNDO. 
DEFINE VARIABLE alldone AS LOGICAL   NO-UNDO. 
FORM WITH FRAME x SIDE-LABELS 2 COLUMNS 1 DOWN COLUMN 25. 
/* Define user-defined functions */ 
FUNCTION dispcust RETURNS LOGICAL: 
  DISPLAY Customer EXCEPT Customer.Comments WITH FRAME x. 
END. 
FUNCTION firstrec RETURNS LOGICAL: 
  FIND FIRST Customer. 
  dispcust(). 
  RETURN yes. 
END. 
FUNCTION lastrec RETURNS LOGICAL: 
  FIND LAST Customer. 
  dispcust(). 
  RETURN yes. 
END. 
FUNCTION nextrec RETURNS LOGICAL: 
  FIND NEXT Customer NO-ERROR. 
  IF AVAILABLE Customer THEN 
     dispcust(). 
  RETURN AVAILABLE(Customer). 
END. 
FUNCTION prevrec RETURNS LOGICAL: 
  FIND PREV Customer NO-ERROR. 
  IF AVAILABLE Customer THEN 
     dispcust(). 
  RETURN AVAILABLE(Customer). 
END. 
FUNCTION quitting RETURNS LOGICAL: 
  alldone = yes. 
  RETURN no. 
END 
/* Main routine */ 
REPEAT WHILE NOT alldone: 
  UPDATE action HELP  
    "Enter F(irst), L(ast), N(ext), P(rior), or Q(uit) to navigate.". 
  idx = LOOKUP(action,"f,l,n,p,q"). 
  IF idx EQ 0 THEN DO: 
    MESSAGE "Enter F(irst), L(ast), N(ext), P(rior), or Q(uit)"  
      VIEW-AS ALERT-BOX. 
    NEXT. 
  END. 
  DISPLAY DYNAMIC-FUNCTION(funcs[idx]) LABEL "Record Found?". 
END.