Data Types

The data types of an entity specify its associated meaning, constraints, possible values, operations, functions, and storage mode.

A variable is nothing but a name given to a storage area that our programs can manipulate. Each variable in TRObject has a specific type, which determines the size and layout of the variable's memory; the range of values that can be stored within that memory; and the set of operations that can be applied to the variable.

A type declaration is used to declare the data type of an identifier. The syntax of a type declaration is as follows:

var
  days : integer;

Integer Types

Type	Description
Byte	Values range from 0 to 255.
ShortInt	Values range from -128 to 127.
SmallInt	Values range from -32,768 to 32,767.
Integer	Values range from -2,147,483,648 to 2,147,483,647.
LongInt	Has the same range as Integer.
Int64	Values range from -9,223,372,036,854,775,808 to 9,223,372,036,854,775,807.
Cardinal	Values range from 0 to 4,294,967,295.
LongWord	Values range from 0 to 4,294,967,295.
UInt64	Values range from 0 to 18,446,744,073,709,551,615.

Example
TRObject Syntax

var
  age: Byte;
  temperature: ShortInt;
  year: SmallInt;
  population: Integer;
  distance: Int64;
  fileSize: Cardinal;
  largeNumber: UInt64;
  balance: LongInt;
  memorySize: LongWord;
{
  age = 25;
  temperature = -15;
  year = 1990;
  population = 1500000;
  distance = 10000000000;
  fileSize = 4000000;
  largeNumber = 1200000000000000000;
  balance = -5000000;
  memorySize = 3000000000;
  
  ShowMessage(age);
  ShowMessage(temperature);
  ShowMessage(year);
  ShowMessage(population);
  ShowMessage(distance);
  ShowMessage(fileSize);
  ShowMessage(largeNumber);
  ShowMessage(balance);
  ShowMessage(memorySize);
}

Base Syntax

var
  age: Byte;
  temperature: ShortInt;
  year: SmallInt;
  population: Integer;
  distance: Int64;
  fileSize: Cardinal;
  largeNumber: UInt64;
  balance: LongInt;
  memorySize: LongWord;
begin
  age := 25;
  temperature := -15;
  year := 1990;
  population := 1500000;
  distance := 10000000000;
  fileSize := 4000000;
  largeNumber := 1200000000000000000;
  balance := -5000000;
  memorySize := 3000000000;
  
  ShowMessage(age);
  ShowMessage(temperature);
  ShowMessage(year);
  ShowMessage(population);
  ShowMessage(distance);
  ShowMessage(fileSize);
  ShowMessage(largeNumber);
  ShowMessage(balance);
  ShowMessage(memorySize);
end;

Floating-point Types

Type	Description
Single	Single precision, approximately 7-digit floating-point number.
Double	Double precision, approximately 15-digit floating-point number.
Extended	High precision, approximately 19-20 digit floating-point number.
Currency	Fixed precision (4 decimal places), suitable for financial calculations.
Real	Typically used interchangeably with Double.

Example
TRObject Syntax

var
  s: Single;
  d: Double;
  e: Extended;
  c: Currency;
  r: Real;
{
  // Değişkenlere değer atayalım
  s = 1234.5678;
  d = 123456789.1234567;
  e = 1234567890123456789.123456789;
  c = 123456.7890;
  r = 987654321.1234567;

  // Sonuçları ekrana yazdıralım
  ShowMessage(s);
  ShowMessage(d);
  ShowMessage(e);
  ShowMessage(c);
  ShowMessage(r);
}

Base Syntax

var
  s: Single;
  d: Double;
  e: Extended;
  c: Currency;
  r: Real;
begin
  // Değişkenlere değer atayalım
  s := 1234.5678;
  d := 123456789.1234567;
  e := 1234567890123456789.123456789;
  c := 123456.7890;
  r := 987654321.1234567;

  // Sonuçları ekrana yazdıralım
  ShowMessage(s);
  ShowMessage(d);
  ShowMessage(e);
  ShowMessage(c);
  ShowMessage(r);
end;

Character and String Types

Type	Description
Char	A single character (ANSI).
WideChar	A single wide character (Unicode).
String	A variable-length ANSI character string.
ShortString	A fixed-length ANSI character string up to 255 characters.
AnsiString	ANSI character string.
WideString	Unicode character string.
UnicodeString	Unicode character string, Delphi's default string type.

Example
TRObject Syntax

var
  c: Char;    
  wideC: WideChar;
  s: String;    
  shortS: ShortString;  
  ansiS: AnsiString; 
  wideS: WideString;
  unicodeS: UnicodeString;

{
  c = 'A';    
  wideC = '𐍈';
  s = 'TRObject programming language'; 
  shortS = 'Hello!'; 
  ansiS = 'İstanbul';  
  wideS = 'Extended text with Unicode support: ö, ü, ş';  
  unicodeS = 'Unicode, the default string type; Turkish characters: ç, ğ, İ';


  ShowMessage('Char: '+ c);
  ShowMessage('WideChar: '+ wideC);
  ShowMessage('String: '+ s);
  ShowMessage('ShortString: '+ shortS);
  ShowMessage('AnsiString: '+ ansiS);
  ShowMessage('WideString: '+ wideS);
  ShowMessage('UnicodeString: '+ unicodeS);
}

Base Syntax

var
  c: Char;    
  wideC: WideChar;
  s: String;    
  shortS: ShortString;  
  ansiS: AnsiString; 
  wideS: WideString;
  unicodeS: UnicodeString;

begin
  c := 'A';    
  wideC := '𐍈';
  s := 'TRObject programming language'; 
  shortS := 'Hello!'; 
  ansiS := 'İstanbul';  
  wideS := 'Extended text with Unicode support: ö, ü, ş';  
  unicodeS := 'Unicode, the default string type; Turkish characters: ç, ğ, İ';


  ShowMessage('Char: '+ c);
  ShowMessage('WideChar: '+ wideC);
  ShowMessage('String: '+ s);
  ShowMessage('ShortString: '+ shortS);
  ShowMessage('AnsiString: '+ ansiS);
  ShowMessage('WideString: '+ wideS);
  ShowMessage('UnicodeString: '+ unicodeS);
end;

Boolean Types

Specifies true or false logical values. This is also an integer type.

Type	Description
Boolean	Can take the values True or False.

Example
TRObject Syntax

var
  b: Boolean; 

{
  b = True;      
  ShowMessage(b);
}

Base Syntax

var
  b: Boolean; 

begin
  b := True;      
  ShowMessage(b);
end;

Date and Time Types

Type	Description
TclDateTime	Stores dates and times, represented as days and fractions of days.

Example
TRObject Syntax

var
  currentDateTime: TclDateTime;  // TDateTime türünde bir değişken
  specificDateTime: TclDateTime;  // Belirli bir tarih ve saat için değişken

{
  currentDateTime = Now;
  specificDateTime = EncodeDate(2024, 1, 1) + EncodeTime(15, 30, 0, 0);

  ShowMessage('Current Date and Time: '+ DateTimeToStr(currentDateTime));
  ShowMessage('Specific Date and Time: '+ DateTimeToStr(specificDateTime));
}

Base Syntax

var
  currentDateTime: TclDateTime;  // TDateTime türünde bir değişken
  specificDateTime: TclDateTime;  // Belirli bir tarih ve saat için değişken

begin
  currentDateTime := Now;
  specificDateTime := EncodeDate(2024, 1, 1) + EncodeTime(15, 30, 0, 0);

  ShowMessage('Current Date and Time: '+ DateTimeToStr(currentDateTime));
  ShowMessage('Specific Date and Time: '+ DateTimeToStr(specificDateTime));
end;

Sr.No	Type & Description
1	Character Typically a single octet (one byte). This is an integer type.
2	Integer The most natural size of integer for the machine.
3	Real A single-precision floating point value.
4	Boolean Specifies true or false logical values. This is also an integer type.
5	Enumerated Specifies a user-defined list.
6	Subrange Represents variables, whose values lie within a range.
7	String Stores an array of characters.