System Unit

The System unit is automatically included in every DWScript program. It defines the fundamental types, base classes, and global functions of the language.

Core Classes

TObject

The ultimate ancestor of all classes in DWScript.

Member	Kind	Description
`Create`	Constructor	Standard constructor.
`Destroy`	Destructor	Virtual destructor.
`Free`	Procedure	Safely calls `Destroy`.
`ClassName`	Function	Returns the name of the object's class as a string.
`ClassType`	Function	Returns the metaclass (TClass) of the object.
`ClassParent`	Function	Returns the metaclass of the parent class.

Exception

Base class for all error handling.

Member	Description
`Create(msg)`	Constructor with error message.
`Message`	Property containing the error description.
`StackTrace`	Property containing the call stack at the point of failure.

Global Functions

Function	Description
`Print(v)`	Outputs a value to the current result stream.
`PrintLn(v)`	Outputs a value followed by a newline.
`Swap(var a, b)`	Swaps the values of two variables of the same type.
`SetLength(var v, len)`	Resizes a dynamic array or string.
`Inc(var x [, n])`	Increments a variable (Integer or Float).
`Dec(var x [, n])`	Decrements a variable.
`Assigned(v)`	Returns True if an object, interface, or procedure variable is not nil.
`ExceptObject`	Returns the current exception object in an `except` block.
`ParamCount`	Returns the number of command-line parameters.
`ParamStr(i)`	Returns a specific command-line parameter.

Examples

Object Inspection

var obj := new TObject;
PrintLn(obj.ClassName); // TObject
obj.Free;

Result

TObject

Exception Handling

try
  raise new Exception('An error occurred');
except
  on E: Exception do
    PrintLn(E.Message);
end;

Result

An error occurred

Swapping Variables

var a := 10;
var b := 20;
Swap(a, b);
PrintLn(Format('a=%d, b=%d', [a, b]));

Result

a=20, b=10

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