Constant Expression

Since 3.17

Constant expressions are integer expressions that are evaluated at compile time, and that can be used in the following places:

These expressions only support a subset of Gambas operators and pre-defined constants.

Here is what you can use inside a constant expression:

Arithmetic operators.	`+`, `-`, `*`, `/`, `\`, `DIV`, `%`, `MOD`
Logical operators.	`AND`, `OR`, `XOR`, `NOT`
Bitwise operators.	`Shl`, `Shr`, `Asl`, `Asr`, `Lsl`, `Lsr`
Size of a native numerical or date datatype.	`SizeOf`
Boolean constants	`TRUE`, `FALSE`
Native datatype constants.	gb.Boolean gb.Byte gb.Short gb.Integer gb.Long gb.Single gb.Float gb.Date
Any private integer constant identifier previously declared.

In the context of constant integer expressions, The / operator acts like the integer division operator \.

Examples

Public Const Alpha As Integer = 1 Public Const Beta As Integer = (Alpha * 2) + 1 Public Const Delta As Byte = Beta + Alpha Private Enum FirstFlag = 1 Shl 0, SecondFlag = 1 Shl 1, ThirdFlag = 1 Shl 2 Private SomeEmbeddedArray[Delta * SizeOf(gb.Short)] As String