Talk:Character and string types

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Is the sentence in Character_and_string_types#Array_of_Char, delivers: a b c d #0 since arrays are filled with null-bytes in Free Pascal correct?!

I've tested (Lazarus 1.2.2 r44758 FPC 2.6.4 i386-win32-win32/win64 and Lazarus 1.3 r45097M FPC 2.7.1 i386-win32-win32/win64 on Win7)

procedure TForm1.Button1Click(Sender: TObject);
  TOldString4 = array[0..4] of char;
  aOldString4: TOldString4;
  aOldString4[0] := 'a';
  aOldString4[1] := 'b';
  aOldString4[2] := 'c';
  aOldString4[3] := 'd';

I got different results, but not #0 for aOldString4[4]. So, do I have to update the facts or do I missunderstood the statement?

Thanks --Michl 23:10, 1 June 2014 (CEST)

That statement is indeed completely bogus, there is no guarantee whatsoever regarding the content of that array element. Maybe the author was confused because of dynamic arrays, whose empty positions are initially initialised with 0 (or #0, or nil, or ...).
Jonas 11:37, 2 June 2014 (CEST)
Thank you for your comment! I think, its maybe a bug, cause if the type "OldString" is declared in the procedure, the statement is false, otherwise seems to vote. I asked in the forum.
--Michl 13:46, 2 June 2014 (CEST)
All global variables are always initialised with 0/#0/nil/... That is documented in the manual, has nothing to do with array of char, and should therefore not be mentioned here because it is orthogonal.
Jonas 14:43, 2 June 2014 (CEST)
Thank you Jonas, I did not question your statement was just surprised that when several attempts always an array filled with # 0 was created. Strange coincidences, please excuse my rude behavior and my not so good English.
I have now differentiated by static and dynamic array of char. If you or anyone else wants to, so someone could let's see, whether in terms of content and of the spelling, is in order.
Thank you! --Michl 21:19, 2 June 2014 (CEST)


Doesn't ANSIChar contain an ANSI character instead of ASCII? I.e. it is codepage dependent but can contain byte values 0..255?

--BigChimp 15:28, 28 December 2013 (CET)

This is the information of the official FPC documentation. I will do additional research.
--Jwdietrich 15:33, 28 December 2013 (CET)
Yes, I suspect the official FPC documentation is wrong/incomplete ;)
BTW: thanks for writing this page - it's very helpful!
--BigChimp 16:53, 28 December 2013 (CET)
Thanks for your positive feedback. In fact, it is ANSI. Although the official Free Pascal documentation states that a char contains an ASCII character, is is stored as a byte to use extended ASCII or ANSI.
--Jwdietrich 16:55, 28 December 2013 (CET)

Wrong links

The links that can be found in each individual subsection points to the wrong location of the (online FPC) documentation. Maintaining wiki's is fun ! ;-) --Molly (talk) 13:35, 15 January 2017 (CET)

Hope I fixed that. --Bart (talk) 18:07, 15 January 2017 (CET)