The keyword instruction PROCEDURE

Be aware that any routine declared with PROCEDURE only allows access to the global variables it knows to all called routines (see also The keyword instruction EXPOSE).

Example:

 
  i = 4
  k = 3
  j = 2
  say "Value of i at program start is " || i
  say "Now calling MyProc1 from the main function ..."
  call MyProc1
  say " Value of i after call of MyProc1 is " || i

  say "Now calling MyProc2 from the main function ..."
  call MyProc2
  say "Value of i after call of MyProc2 is " || i
exit 0

MyProc1: PROCEDURE expose k j
  say " Now calling MyProc2 from within the function myProc1 ..."
  i = 0
  call MyProc2
RETURN

MyProc2: PROCEDURE expose i
  say "  MyProg2 starts ..."
  say "   Value of i in MyProc 2 is " || i

                        /* This is the global variable i if MyProc2   */
                        /* is called from the main function -- but:   */
                        /* This is a local variable if MyProc2 is     */
                        /* called from MyProc1!                       */
  i = i + 2

  say "   Value of i in MyProc 2 changed to " || i
  say "  ... MyProg2 ends."
RETURN

Note: If you want to use a label with CALL and SIGNAL you cannot use the keyword PROCEDURE!

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