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  ◄Scoping Rules►   ◄Global Variables and Constants►   ◄Contents►   ◄Index►
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Global Variables and Constants
 
Both variables and symbolic constants can be global in BASIC programs. A
global variable or global symbolic constant is defined for the entire
module.
 
  ■ A symbolic constant is a global constant if it is declared in the
    module-level code using a CONST statement.
 
  ■ For a variable, the only way to make it global is to declare it in the
    module-level code with the SHARED attribute in a DIM, REDIM, or COMMON
    statement. For example, the following program fragment makes TabStops a
    global variable.
 
      DIM SHARED TabStops(MAXLINE)
      .
      .
      .
      SUB SetTabPos STATIC
      .
      .
      .
      END SUB
      FUNCTION ThisIsATab(LastColumn AS INTEGER) STATIC
      .
      .
      .
 
The SHARED statement (as opposed to the SHARED attribute, used above) allows
particular procedures to share variables with the module-level code. This is
not the same as making the variable global. It is only global for the
module-level code and all procedures with SHARED statements for the variable.