On Fri, 28 May 2010, spir ☣ wrote:
Hello,
While waiting for more information about how to use "associated objects" with TStringList, I
started to implement // lists for names (TString) and values (TFPList). This builds a kind of flexible record
type, I called "Struct" because the name "Record" is not available ;-)
Values are in in fact Struct-s themselves. All works fine when storing data,
but I cannot get it back. Precisely,
i := self.names.indexOf(name);
val := Struct(self.values[i]);
raises "got untyped expected Struct". Sure, that's why I'm trying to cast... Without
casting to Struct, the compiler indeed throws "got pointer expected Struct". I'm very
surprised since I already did this.
So, I quickly wrote a simpler test case wrapping structure, just putting
objects in a TFPList and casting back: all works fine:
If you want this, I suggest you look at fpjson. it does all this for you. It
has an extensive testsuite, so plenty of code to peep at.
Michael.
========================
program __essai__;
{$mode objfpc}{$H+}
uses
Classes, SysUtils;
type Struct = Class
val : Integer;
constructor struct(i:Integer);
function text : String;
end;
constructor Struct.struct(i:Integer);
begin
inherited;
self.val := i;
end;
function Struct.text : String;
begin
result := '<' +intToStr(self.val)+ '>';
end;
var
s : Struct;
l : TFPList;
begin
s := Struct.struct(1);
writeln(s.text);
l := TFPList.create;
l.add(s);
s := Struct(l[0]); //////////////////
writeln(s.text);
end.
=== output ===
<1>
<1>
Thank you,
Denis
________________________________
vit esse estrany ☣
spir.wikidot.com
_______________________________________________
fpc-pascal maillist - fpc-pascal@lists.freepascal.org
http://lists.freepascal.org/mailman/listinfo/fpc-pascal
_______________________________________________
fpc-pascal maillist - fpc-pascal@lists.freepascal.org
http://lists.freepascal.org/mailman/listinfo/fpc-pascal
