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     SBasic User's Manual     SBasic Version 2.7             Page 19
     Printed:  December 5, 1999
     Variables, arrays, and named constants


     SBasic requires you to declare the names of all variables used in your
     program.  You declare variables with the DECLARE command.  For
     example,

          declare  foo

     creates the SBasic variable FOO.

     Variable names must begin with an alphabetic character or an
     underscore ('_'); remaining characters in a variable name can also
     include digits.

     NOTE:  Though legal, starting variable names with an underscore can
     cause obscure problems if you embed assembly language in your SBasic
     source file.  See the section below on ASM and ENDASM, regarding
     references to SBasic variables from within an ASM block.

     All variables use two bytes of RAM.  The first variable defined is
     always located at assembler address VARBEG.  Variables are assigned
     addresses based on the order of their declarations.

     You must declare a variable before your code can reference that
     variable.  This means that you will usually place all DECLARE
     statements in a block at the beginning of your SBasic source file.

     Note that, unlike traditional Basics, SBasic does not automatically
     initialize all variables to zero.  The value of any variable following
     system reset is unknown!  Your SBasic program must provide any needed
     variable initialization.

     SBasic also supports single-dimension arrays, or vectors.  Each
     element in an array occupies one 16-bit location (two bytes).  You use
     the DECLARE statement to define an array in much the same way you use
     it to define a simple variable.  For example:

         declare  foo(5)

     defines the array FOO, consisting of five sequential 16-bit locations.
     The first element in any array is always element zero.  Thus, FOO in
     the above example consists of the five elements named FOO(0) through
     FOO(4).

     You can use arrays anywhere a variable name would be legal, including
     the left side of an assignment operator.  For example:

         declare  foo(5)

         foo(2) = 100/n