12.7 Manipulating String Data with Multiple Maps
  Mapping a string storage area in more than one way lets you
  extract a substring from a string or concatenate strings. In
  the following example, the three MAP statements reference
  the same 108 bytes of data:
  EXAMPLE: Click to display example.

  You can move data into a map in different ways. For in-
  stance, you can use terminal input, arrays, and files. In the
  following example, the READ and DATA statements are used
  to move data into a map:
  READ EMPLOYEE_RECORD$
  DATA "WILLIAM DAVIDSON 2241 MADISON BLVD " &
  "SCRANTON PA14225A912/10/78$13,325.77$925.31"

  Because all the MAP statements in the previous example ref-
  erence the same storage area (emprec) , you can access parts
  of this area through the mapped variables as shown in the
  following examples:
  PRINT full_name$
  PRINT wage_class$
  PRINT salary_ytd$

  Output 1
  WILLIAM DAVIDSON
  A9
  $13,325.77

  Example 2
  PRINT last_name$
  PRINT tax_ytd$

  Output 2
  DAVIDSON
  $925.31
  You can assign a new value to any of the mapped variables.
  The following example prompts the user for changed infor-
  mation by displaying a menu of topics. The user can then
  choose which topics need to be changed and then separately
  assign new values to each variable.
  EXAMPLE: Click to display example.

  Output
  EXAMPLE: Click to display example.

  See Chapter 8 and the DEC BASIC and VAX BASIC for
  OpenVMS Systems Reference Manual for more information
  about the MAP statement.