More Intrinsic Type Helpers (or 42.ToString)

May 31, 2013

More Intrinsic Type Helpers (or 42.ToString)

Delphi XE4 adds quite a few helpers for native language data types, like Integers and Doubles.

Although the core focus of Delphi XE4 is clearly on iOS development, there are some nice features for all of the platforms, including Win32. One of these features is the support for more intrinsic type helpers, like the TStringHelper for the string type that was introduced in Delphi XE3. Delphi XE4 adds quite a few helpers for native language data types, like Integers and Doubles.

Here is a screen shot of the editor with some slightly unusual Delphi code (although the same could be obtained in Delphi XE3 adding a custom helper):

And here is the list of the intrinsic type helpers, available in the SyUtils unit:

SysUtils.pas(3352): TGuidHelper = record helper for TGUID
SysUtils.pas(3856): TStringHelper = record helper for string
SysUtils.pas(3984): TSingleHelper = record helper for Single
SysUtils.pas(4048): TDoubleHelper = record helper for Double
SysUtils.pas(4112): TExtendedHelper = record helper for Extended
SysUtils.pas(4176): TByteHelper = record helper for Byte
SysUtils.pas(4198): TShortIntHelper = record helper for ShortInt
SysUtils.pas(4220): TSmallIntHelper = record helper for SmallInt
SysUtils.pas(4242): TWordHelper = record helper for Word
SysUtils.pas(4264): TCardinalHelper = record helper for Cardinal { for LongWord type too }
SysUtils.pas(4286): TIntegerHelper = record helper for Integer { for LongInt type too }
SysUtils.pas(4308): TInt64Helper = record helper for Int64
SysUtils.pas(4330): TUInt64Helper = record helper for UInt64
SysUtils.pas(4352): TNativeIntHelper = record helper for NativeInt
SysUtils.pas(4379): TNativeUIntHelper = record helper for NativeUInt
SysUtils.pas(4405): TBooleanHelper = record helper for Boolean
SysUtils.pas(4416): TByteBoolHelper = record helper for ByteBool
SysUtils.pas(4427): TWordBoolHelper = record helper for WordBool
SysUtils.pas(4438): TLongBoolHelper = record helper for LongBool

Notice that while you can replace these helpers with your own, there is no way to extend them with extra methods. Replacing the default helpers is not really suggested, although it is clearly possible. A workaround is to introduce a new name for one of these data types, and add a helper for the new "clone" type. In general, we consider intrinsic helpers as a low-level feature, subject to future implementation changes.

posted by marcocantu @ 2:04PM | 7 Comments [0 Pending]

More Intrinsic Type Helpers or 42.ToString

 These intrinsic helpers are all added value to the 
language. It will help the transition of the Delphi 
language to a rooted type system.

To fully qualify for such a system, all intrinsic 
functions, like Length,SetLength,High,Low,etc, have to 
be implemented as class operators in records. 

If ShortStrings,AnsiStrings,Utf8Strings are considered 
as deprecated, which seems to be the plan (or at least 
not implemented for all platforms), the only way to 
backport the full drop-in replacement for them is to 
fully qualify all intrinsic operations for records.

Comment by Leif Uneus [http://www.opsis.se] on May 31, 17:11

More Intrinsic Type Helpers or 42.ToString

 Why didn't you use the new unambiguous numeric data 
types names in the helper names? Wasn't it better 
TUInt32Helper than TCardinalHelper, etc.?

Comment by Luigi D. Sandon on May 31, 18:12

More Intrinsic Type Helpers or 42.ToString

I am sure Error Insight will love this!

Comment by Anders Andersen on June 1, 11:37

More Intrinsic Type Helpers or 42.ToString

 All of thease are just a syntactic sugar.
Not essential . I think it is good. But, why not use
more energy to do the most important things.

Comment by on June 3, 01:13

More Intrinsic Type Helpers or 42.ToString

My XE3 already has helpers for all the 
intrinsic types... :0(

Just changed my helperclass like this and the 
workaround works fine (thx) 

Type
  eXByte=Byte; 

  TByteHelper = record helper for eXByte
    Function asAscCtrlStr:String;
    Function asAscCtrlHexStr:String;
    Function asStr(LeftPad:Integer=0):String;
    Function asHexStr(Dollar:Boolean=True):String;
    Function asBinStr:String;
    Function Debug:String;
    Procedure SetBit(BitNr:Byte;Bit:Boolean);
    Procedure Toggle(BitNr:Byte);
    Function  BitH  (BitNr:Byte):Boolean;
    Function  BitL  (BitNr:Byte):Boolean;
    Procedure SBit  (BitNr:Byte);
    Procedure CBit  (BitNr:Byte);
    Function FSBit(Var 
Index:Bit;MaxBit:Bit=Bx07):TSearchBit; overload;
  private
    function getBits: T8Bit;
    procedure setBits(const Value: T8Bit);
  Public
    Property Bits:T8Bit read getBits write setBits;
  end;


I can do like this again (Only Delphi does bit loops)

Var
  XByte : Byte;
  BitNo : Bit; // Yes
Begin
  XByte:=85;
  for BitNo in XByte.Bits do
    Memo1.Lines.Add(BitNo.Name+' is set');
  If XByte.Bit(Bx03) Then
    XByte.Toggle(B3)
End;

What about duplicate names for helper functions ?
Lets say Delphi Xe4 has Byte.toString and My 
eXByte.toString, what would happend ?

Comment by Søren [http://www.http://dsautomation.dk/] on June 5, 16:45

More Intrinsic Type Helpers or 42.ToString

Not sure I'm following how flexible / inflexible this 
is.

For example, is it possible to create your own TCurrency 
helper with methods to convert between currencies?

Comment by Craig Read on June 9, 14:20

More Intrinsic Type Helpers or 42.ToString

Think about follow defination:
TCustomerStringHepler = record helper for 
TStringHelper
end;

Comment by on June 20, 08:58

Marco Tech Blog

More Intrinsic Type Helpers (or 42.ToString)

7 Comments

More Intrinsic Type Helpers or 42.ToString

More Intrinsic Type Helpers or 42.ToString

More Intrinsic Type Helpers or 42.ToString

More Intrinsic Type Helpers or 42.ToString

More Intrinsic Type Helpers or 42.ToString

More Intrinsic Type Helpers or 42.ToString

More Intrinsic Type Helpers or 42.ToString

Post Your Comment