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Robert Cemper · Apr 15, 2019

the structure of $LB() is rather simply a binary string

-----------element--------------
TotalLength = 1, 3, 7 bytes depending on size    *corrected*
Type = 1 byte  (check in JSON converter for codes, or just check with ZZDUMP)
Content : size = TotalLength-1-size of length field
-----------element--------------
TotalLength = 1, 3, 7 bytes depending on size    *corrected*
Type = 1 byte  (check in JSON converter for codes, or just check with ZZDUMP)
Content : size= TotalLength-1-size of length field
-----------element--------------

...

Therefore concatenation of $lb) is so easy

Robert Cemper · Apr 10, 2019

Sorry,  I had more changes. 
My approach in details

Class DC.String Extends %String  {
ClassMethod Get() As %String [ CodeMode = objectgenerator ]
{    do %code.WriteLine($c(9) _ "Quit $g(^Test.String, 0)")
    quit $$$OK  }
ClassMethod Set(%val As %String) [ CodeMode = objectgenerator ] {
    do %code.WriteLine($c(9) _ "Set ^Test.String = %val")
    do %code.WriteLine($c(9) _ "do zTest()")
    quit $$$OK }

/// this generates Method propTest()
/// but satisfies the Compiler for this class
ClassMethod Test() { quit  ;; from Data definition }
}

compiles this routine:

 ;DC.String.1
 ;(C)InterSystems, generated for class DC.String. Do NOT edit. 10/04/2019 12:00:42PM
 ;;42345370;DC.String
 ;
zGet() public {  Quit $g(^Test.String, 0) }
zSet(%val) public { Set ^Test.String = %val
      do zTest() }
zTest() public {  quit  ;; from Data definition }

and the  using class

Class DC.StringTest Extends %RegisteredObject  {
Property prop As DC.String;
Method Test()
{  b   quit ;; from using Class }
}

compiled as 

 ;DC.StringTest.1
 ;(C)InterSystems, generated for class DC.StringTest. Do NOT edit. 10/04/2019 12:02:35PM
 ;;49614632;DC.StringTest
 ;
%NormalizeObject() public {
If '$system.CLS.GetModified() Quit 1
If m%prop Set:i%prop'="" i%prop=(..propNormalize(i%prop))
Quit 1 }
%ValidateObject(force=0,checkserial=1) public {
set sc=1
If '$system.CLS.GetModified() Quit sc
If m%prop Set iv=..prop If iv'="" Set rc=(..propIsValid(iv)) If ('rc) Set sc=$$EmbedErr^%occSystem(sc,rc,5802,"prop",iv)
Quit sc }
zTest() public {
 b   quit ;; from using Class
}
zpropGet() public {
Quit $g(^Test.String, 0) }
zpropSet(%val) public {
Set ^Test.String = %val
do zTest() }
zpropTest() public {
 quit  ;; from Data definition
}

and the test

 SAMPLES>s obj=##class(DC.StringTest).%New()
SAMPLES>set obj.prop=123
 b   quit ;; from using Class
 ^
<BREAK>zTest+1^DC.StringTest.1
SAMPLES 3d1>

Well, the code generator can be tricky.
It's not one of my favorites. But sometimes you have no choice.

Robert Cemper · Apr 9, 2019

OK.
StorageTo../..ToStorage only works in persistent classes where you move content from/to globals.
No chance without storage. 

It doesn't get called in Registered Classes and not when the object wasn't saved.
see my test with %Persistent

set obj=##class(Test.String).%New()
write obj.prop    ;nothing loaded yet

set obj.prop=77 write obj.prop   ; unchanged as neither stored nor loaded
77
do obj.%Save(),obj,%Reload() ; force reload to trigger StorageToLogical
write obj.prop  ; and here we go
prop


This proves that there is limited use of the approach.

Robert Cemper · Apr 8, 2019

Ken Olson , the founder of DEC (Digital Equipment Corp.) was  famous for its statement:

  • "I can't imagine any good reason for someone to have a computer at his home"

 Similar in the late 1950ies IBM estimated the worldwide market for computers of 15..30 systems in total.

So lack of phantasy what could be in the future is quite common also for very successful people and companies.

Robert Cemper · Apr 1, 2019

you better not change   %CSP.Login but make a personal copy and change this

404 = HTTP page not found. Most likely you put your copy to the wrong directory or namespace   

And then you have to put the reference in MgmtPortal Security-> WebApplications as Login page:
Again with the correct namespace and the correct directory.