Redefinition of internal functions

REXX allows it to redefine any built-in function in a REXX program. If, 
for example, you define a function named DATE in your program the call 

 
  curDate = date()

calls your newly defined function and NOT the built-in function date() 

To call the built-in function -- for example in your new defined function 
-- call it like this: 

 
  call "DATE"

or 

 
  curDate = "DATE"()

Important:  You must use the name of the built-in function in uppercase! 

  (see also Redefinition of functions from a DLL)   

 Note:   See Expand the function FILESPEC, Check if a queue exists, or 
         Call by value for working examples.