Ink.Parsed.Story.AddExternal C# (CSharp) Method

        public void AddExternal(ExternalDeclaration decl)
        {
            if (externals.ContainsKey (decl.name)) {
                Error ("Duplicate EXTERNAL definition of '"+decl.name+"'", decl, false); 
            } else {
                externals [decl.name] = decl;
            }
        }