Data Types and Operators

This article is about the datatypes and operators in Jabaco. Get detailed informations about the usage compared with other BASIC dialects.

Jabaco Data Types

A data type in programming languages is an attribute of a data which tells the computer (and the programmer) something about the kind of data it is. This involves setting constraints on the datum, such as what values it can take and what operations may be performed upon it. Numeric data types are types of data that consist of numbers, which can be computed mathematically with various standard operators such as add, minus, multiply, divide and more. In Jabaco, numeric data are divided into several types, depending on the range of values they can store. The non-numeric data comprises text or string data types, the Date data types, the Boolean data types that store only two values (true or false), Object data type and Variant data type...

Data Types Usage Examples

The Jabaco User-Defined Types (UDTs) are quite similar to VB6 (Visual Basic 6) and VB.net

' user defined type
Private Type CarInfo
   Manufacturer As String
   Name As String
   PowerKWH As Long
End Type
 
' declare a user defined type
Public Function getCarInfoSLK() As CarInfo 
   Dim retCar As CarInfo 
   retCar.Manufacturer = "Mercedes"
   retCar.Name = "SLK"
   retCar.PowerKWH = 265
   getCarInfoSLK = retCar
End Function
 
' usage
Public Sub Command1_Click()
   MsgBox getCarInfoSLK.Manufacturer & " - " & getCarInfoSLK.Name
End Sub

Enumerations (Enums) are structures you define when you need a set of constant values. (similar to Visual Basic 6.0 and VB .net)

' enumeration
Private Enum CarTypeInfo
   Coupe
   Convertible
   Truck
   Van
End Enum
 
' user defined type
Private Type CarInfo
   Manufacturer As String
   Name As String
   PowerKWH As Long
   CarType As CarTypeInfo ' << added enumeration
End Type
 
' declare a user defined type
Public Function getCarInfoSLK() As CarInfo 
   Dim retCar As CarInfo 
   retCar.Manufacturer = "Mercedes"
   retCar.Name = "SLK"
   retCar.PowerKWH = 265
   retCar.CarType = Convertible ' << specify the car type
   getCarInfoSLK = retCar
End Function
 
' usage
Public Sub Command1_Click()
   If getCarInfoSLK.CarType = Convertible Then
      MsgBox "Yes; it is a convertible"
   Else
      ' ...
   End If
End Sub

Suffixes for Literals

Literals are values that you assign to data. In some cases, we need to add a suffix behind a literal so that Jabaco can handle the calculation more accurately. For example, we can use num = 1.2345# for a Single type data.

Dim myVar As Double = 123.456& ' myVar = 123

Dim myVar$ = "i'm a string"

Dim myVar& = 123.456 ' return 123

Dim myVar& = 123.456 ' return 123.456

Arithmetic Operators

To compute inputs from users and to generate results, we need to use various mathematical operators.

Conditional Operators

To control the Jabaco program flow, we can use various conditional operators. Basically, they resemble mathematical operators. Conditional operators are very powerful tools, they let the BASIC program compare data values and then decide what action to take, whether to execute a program or terminate the program and more.

If x = y Then MsgBox "Yes; X is Y" Else MsgBox "No; X isn't Y"

If x > y Then MsgBox "X is greater than Y"

If x < y Then MsgBox "Y is greater than X"

If x >= y Then MsgBox "X is greater or same like Y"

If x <= y Then MsgBox "Y is greater or same like X"

If x <> y Then MsgBox "Yes; X isn't Y" Else MsgBox "No; X is Y"

If a = b and c = d Then MsgBox "Yes; a is b AND c is d"

If a = b or c = d Then MsgBox "Yes; a is b OR c is d"

If a = b xor c = d Then MsgBox"Yes; Either a is b OR c is d, but not both"

If NOT a = b Then MsgBox "Yes; a isn't b"

Jabaco type conversion (typecasting)