Blog: Byte Loss in String-Literal Concatenation

[baoquan.zuo 34]

Hi,

 

I'd like to share a post. It addressed a byte loss issue captured from a discussion.

// Compile with code page 936
program Problem;

const
  strPublicKey: RawByteString =
    #$30#$3C#$30#$0D#$06#$09#$2A#$86#$48#$86#$F7#$0D#$01#$01#$01#$05 +
    #$00#$03#$2B#$00#$30#$28#$02#$21#$00#$A4#$65#$B8#$CD#$B4#$29#$A9 +
    #$64#$1A#$C5#$80#$55#$22#$1B#$BB#$C5#$98#$36#$B9#$23#$0C#$CA#$D4 +
    #$A8#$B8#$7C#$E6#$32#$E3#$89#$3D#$77#$02#$03#$01#$00#$01;
begin
  Writeln(Length(strPublicKey)); // expected 62 got 58 - why?
  Readln;
end.

https://devjetsoftware.com/delphi/byte-loss-in-string-literal-concatenation/

[David Heffernan 2420]

What is wrong with the world of Delphi programmers that in 2025 there are still people who can't understand the difference between text and bytes? 

 

The article you link to goes on and on about text but your data is bytes. Why not just use the correct data type? 

[baoquan.zuo 34]

2 minutes ago, David Heffernan said:

What is wrong with the world of Delphi programmers that in 2025 there are still people who can't understand the difference between text and bytes? 

 

The article you link to goes on and on about text but your data is bytes. Why not just use the correct data type? 

Yes — it’s clear we should use the proper data type to represent raw bytes.

 

What the article (and my curiosity) really digs into is why the data loss occurs and how DCC handles string literals (as there is no formal Delphi language specification). That matters to me because I’m also writing some Delphi compiler-frontend code in my products.

 

In any case, these insights should help when migrating legacy ANSI-based Delphi projects.

[David Heffernan 2420]

5 minutes ago, baoquan.zuo said:

In any case, these insights should help when migrating legacy ANSI-based Delphi projects

I don't see this as helpful to anyone. Use bytes to represent bytes. Use strings to represent text. Don't use ANSI strings. 

[baoquan.zuo 34]

13 minutes ago, David Heffernan said:

I don't see this as helpful to anyone. Use bytes to represent bytes. Use strings to represent text. Don't use ANSI strings. 

Thanks for sharing your view.