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identifier as described in Section 2.1. The <type> must be one of the fundamental data type names

described in Section 2.2 or an Enum type (described in Section 3.2). Lastly, the <value> element must

be value or an expression that has a constant value and is the same type as (or compatible with) the

specified <type>.

In many cases, the <value> will be a simple numeric literal like -55 or 3.14159. In the case of string

constants, it may be a literal string like "Hello, world!". However, it is sometimes convenient to

define a constant in terms of another constant. Consider the example below.

Private Const Pi as Single = 3.14159

Const TwoPi as Single = Pi * 2.0

You may also use certain System Library functions in the constant’s value expression. The restriction is

that the expression must be able to be evaluated at compile time.

Private Const Pi as Single = ACos(-1.0)

Private Const InitialValue as Single = Sin(Pi / 2.0)

The definition of the value of pi in the manner shown in the first example is useful because it results in the

maximum accuracy of the constant value.

String constants are sometimes useful as well.

Public Const VersionNum as String = "V1.0"

Public Const VersionDate as String = "Oct 2005"

Public Const VersionStr as String = VersionNum & " " & VersionDate

Public Const VersionDateUC as String = UCase(VersionDate)

You may define multiple constants of the same or different types on the same line.

Const c1 as Integer = 7, c2 as Single = 3e10

BasicX Compatibility Note

In BasicX mode, UnsignedInteger, UnsignedLong and String constants are

not supported. Also, constant expressions cannot utilize built-in functions.

Defining Variables

To define a variable at the module level (as opposed to within a subroutine or function, described later)

the syntax is:

{Public | Private | Dim} <name> As <type>

Dim has exactly the same effect as Private, i.e., the variable will only be directly accessible to code

within the module.