Constants can be used to declare a constant value (a value that cannot be changed) within the program. This essentially allows a number to be assigned a name, often improving readability and debugging of the source code.

The Const statement can be used to declare constants in Cubloc BASIC:

Const  PI  As  Single = 3.14159
Const  WRTTIME  As  Byte  = 10
Const  MSG1 As String = "ACCESS PORT"  

When the constant is not given a type, the compiler will find an appropriate type for it as shown below:

Const  PI = 3.14159          ' Declare as SINGLE
Const  WRTTIME  = 10         ' Declare as Byte
Const  MYROOM  = 310         ' Declare as Integer since it’s over 255.
Const  MSG1 = "ACCESS PORT"  ' Declare as String

The Con statement can be also used to declare constants as shown below:

PI      Con 3.14159         ' Declare as Single.
WRTTIME Con 10              ' Declare as Byte
MYROOM  Con 310             ' Declare as Integer
MSG1    Con "ACCESS PORT"   ' Declare as String

With constant arrays, the user is able to store a list of values before the program begins. A program requiring a large number of constant values can be simplified as shown below:

Const Byte DATA1 = (31, 25, 102, 34, 1, 0, 0, 0, 0, 0, 65, 64, 34)
I = 0
A = DATA1(I)     ' Store 31 in A.
I = I + 1
A = DATA1(I)     ' Store 25 in A.
Const Byte DATA1 = ("CUBLOC SYSTEMS")

String data can be stored in Byte constant arrays. Each Byte contains the ASCII code of each character in the String. In the example above, if DATA1(0) is read, the ASCII code of 'C' is returned. Likewise if DATA1(1) is read, ASCII code of 'U' is returned. Integer and floating point (Single) numbers can also be stored in arrays as shown below:

Const Integer DATA1 = (6000, 3000, 65500, 0, 3200)
Const Long DATA2 = (12345678, 356789, 165500, 0, 0)
Const Single DATA3 = (3.14, 0.12345, 1.5443, 0.0, 32.0)

For multiple-line constant arrays, end each line with a comma, or an underscore character as shown :

1)

Const Byte DATA1 = (31, 25, 102, 34, 1, 0, 0, 0, 0, 0, 65, 64, 34,
                      12, 123, 94, 200, 0, 123, 44, 39, 120, 239,
                      132, 13, 34, 20, 101, 123, 44, 39, 12, 39)

2)

Const Byte DATA2 = (31, 25, 102, 34, 1, 0, 65, 64, 34_
  , 101, 123, 44, 39, 12, 39)

Please make note of the following differences between arrays and constant arrays.

String constant arrays are deprecated.

See also #define.

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