Directive block - Gen<None> - 20 - (0:0,0)
    Transition span - Gen<None> - [@] - SpanEditHandler;Accepts:None - (0:0,0) - Symbols:1
        CSharpSymbolType.Transition;[@];
    Code span - Gen<Import: static System;> - [using static System] - SpanEditHandler;Accepts:AnyExceptNewline - (1:0,1) - Symbols:5
        CSharpSymbolType.Keyword;[using];
        CSharpSymbolType.WhiteSpace;[ ];
        CSharpSymbolType.Keyword;[static];
        CSharpSymbolType.WhiteSpace;[ ];
        CSharpSymbolType.Identifier;[System];
