Denso BHT-BASIC 100 SERIES, Руководство программиста

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Chapter 5. Data Types
73
5.5.2 Local Variables
A local variable can be accessed only in a file where it is defined. Write PRIVATE preceding a
desired variable name or DEFREG statement.
(Example) PRIVATE aaa%
PRIVATE bbb$[10]
PRIVATE ccc$(5,3)[30]
PRIVATE DEFREG ddd
PRIVATE DEFREG eee%(5)
Before access to a local variable, you should define it.
If used inside more than one SUB or FUNCTION function in the same file where the local vari-
able is defined, all of those variables will also have the same value.
(Example) PRIVATE aa%
FUNCTION addaa(x)
addaa=aa%+x
END FUNCTION
SUB printaa(x)
print aa%+x
END SUB
aa%=2
print addaa(2)
printaa(2)
In the above example, the variable aa% used in "addaa" and "printaa" will have the same
value.
■ Variables with overlapping scope
If your program has a global variable and a local variable with the same name, in those files
where the variable is declared with the
GLOBAL statement, those variables will be treated as
the same; in a file where the variable is declared with the PRIVATE variable, the variable is
available only in that file.
(Example) If in each of Files 1 and 2 the variable aa% is declared by the
GLOBAL
statement
but in File 3 it is not declared by the
GLOBAL
statement:
File 1 File 2 File 3
GLOBAL aa%[50] GLOBAL aa%[50] PRIVATE aa%[50]
If you link Files 1, 2, and 3 above into a program file, the variables aa% in Files 1 and 2 will
have the same value and aa% in File 3 will be treated as a variable different from those in Files
1 and 2.