REGEXP_FILE
  RegExpPatternImpl: <a[b&&c&&d]>
    RegExpBranchImpl: <a[b&&c&&d]>
      RegExpCharImpl: <a>
        PsiElement(CHARACTER)('a')
      RegExpClassImpl: <[b&&c&&d]>
        PsiElement(CLASS_BEGIN)('[')
        RegExpIntersectionImpl: <b&&c&&d>
          RegExpCharImpl: <b>
            PsiElement(CHARACTER)('b')
          PsiElement(ANDAND)('&&')
          RegExpCharImpl: <c>
            PsiElement(CHARACTER)('c')
          PsiElement(ANDAND)('&&')
          RegExpCharImpl: <d>
            PsiElement(CHARACTER)('d')
        PsiElement(CLASS_END)(']')