Ich weiss zwar nicht, warum Du es unbeding rekursiv willst, aber bitte:
Delphi-Quellcode:
function RemoveSpaces(Line: string): string;
var
Sp: Integer;
begin
Sp := Pos(#32, Line);
if Sp > 0 then
Result := Copy(Line, 1, Sp-1) + RemoveSpaces(Copy(Line, Sp+1, MaxInt))
else
Result := Line;
end;
...
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...