When creating a custom enumerator for string parsing I see some strange error messages. When using record It gives the following error:
E2010 Incompatible types: 'TSplitStringEnumerator' and 'Pointer'
When using classes (insert a few .Create calls in the code) instead of records I get some Internal Errors from time to time:
Does anyone know how to keep the enumeration work with record data types instead of classes?
type
TSplitStringEnumerator = record
StringToParse: string;
Separator: Char;
S: Integer;
E: Integer;
L: Integer;
function GetCurrent (): string; inline;
function MoveNext (): Boolean; inline;
property Current: string read GetCurrent;
end;
TSplitStringGenerator = record
Enum: TSplitStringEnumerator;
function GetEnumerator: TSplitStringEnumerator; inline;
end;
function SplitString( const StringToParse: string; Separator: Char ): TSplitStringGenerator; //inline;
begin
Result.Enum.StringToParse := StringToParse;
Result.Enum.Separator := Separator;
Result.Enum.S := 0;
Result.Enum.E := 0;
Result.Enum.L := Length( StringToParse );
end;
procedure Test();
var
S: string;
begin
for S in SplitString( 'A;B;C', ';' ) do begin
OutputDebugString( PChar( S ) );
end;
end;
{ TSplitStringGenerator }
function TSplitStringGenerator.GetEnumerator(): TSplitStringEnumerator;
begin
Result := Enum;
end;
{ TSplitStringEnumerator }
function TSplitStringEnumerator.GetCurrent(): string;
begin
Result := Copy( StringToParse, S, E - S );
end;
function TSplitStringEnumerator.MoveNext(): Boolean;
begin
S := E + 1;
Result := S <= L;
E := S;
while ( E <= L ) and ( StringToParse[ E ] <> Separator ) do Inc( E );
end;
I have found the similar bug report #72213 on QC. The bug was fixed in Delphi 2010 (see resolution comments).