Use the deffun statement to define a user-written external function (for example, an external sub-routine invoked using CALL).
The deffun statement provides the compiler with information such as the function name, the function number, and the type of arguments. In a program, each user-written function must have a unique definition.
deffun function {(argument{,argument...})}
| function | The name of the user-written function. |
| argument | The list of arguments passed to the external function. |
Example 1
This block declares the function MYFUNC in the calling program. It uses the function with the statement PRINT MYFUNC(A,B,C):
deffun myfunc(a,b,c) print myfunc(a,b,c)
Example 2
This block defines the previously referenced user-written external function, called MYFUNC, with the arguments A, B, and C:
function myfunc(a,b,c) return a*b*c