Unit SymbolInfo;

{ This unit used to be a lot more complicated.  A TSymbolInfo object had to know
  all sorts of things.
    o  For one thing, we had a special flag to say that a symbol had no volume,
       and we should fake the volume numbers.
    o  At one time TAL did not have continuous futures.  So we built them
       ourselves, based on several sources.  This unit recorded which sources,
       and other information required to do that work.
    o  Until just recently, this list could be used in two ways.  When we went
       to TAL we needed to know which stocks to ask about.  And when we created
       the file to tell the real-time servers which symbols to look at, that
       info also came from this unit.  The two lists were not identical.  (And
       I recently found out that feature was broken, and you could not successfully
       request information about a symbol if that symbol is not available in
       real-time.  But part of the code for that existed until just now.)
    o  Until just recently, this unit was reponsible for choosing which symbols
       to watch and which ones to ignore if the user requested automatic symbols
       and gave us a maximum number of symbols to watch.

  Those requirements are gone.  This unit seems trivial now.  It still maintians
  a list of symbols.  We need to ask TAL for data about all of these symbols.

  The old code was a huge mess.  I'm glad that it is gone.  If we ever need to
  do one of those things again, we need to find a better way to do it.  We do
  not want to go back to the old code.
}

Interface

  Uses
    Classes;

  Function CreateSymbolList : TStrings;

  Procedure AddSymbol(SymbolList : TStrings; Symbol : String);

  // This will add each item in the source list to the destination as if you
  // called AddSymbol on each item one at a time.
  // If you sort the list first, this will go faster.
  Procedure AddSymbolList(Destination, Source : TStrings);

  Function GetFuturesAltSymbol(Symbol : String) : String;

Implementation

  Uses
    StrUtils, SysUtils;

  Function CreateSymbolList : TStrings;
    Var
      RealList : TStringList;
    Begin
      RealList := TStringList.Create;
      RealList.Sorted := True;
      RealList.Duplicates := dupIgnore;
      Result := RealList
    End;

  Procedure AddSymbol(SymbolList : TStrings; Symbol : String);
    Begin
      Symbol := UpperCase(Trim(Symbol));
      If Symbol <> '' Then
        SymbolList.Add(Symbol)
    End;

  Procedure AddSymbolList(Destination, Source : TStrings);
    Var
      I : Integer;
    Begin
      For I := 0 To Pred(Source.Count) Do
        AddSymbol(Destination, Source[I])
    End;

  Function GetFuturesAltSymbol(Symbol : String) : String;
    Begin

      If (LeftStr(Symbol, 1) = '/') And
         (RightStr(Symbol, 3) = '[0]') Then
        Result := LeftStr(Symbol, Length(Symbol) - 3) + '[2]'
      Else
        Result := ''
    End;



End.