REGEXP_FILE
  RegExpPatternImpl: <abc[\>
    RegExpBranchImpl: <abc[\>
      RegExpCharImpl: <a>
        PsiElement(CHARACTER)('a')
      RegExpCharImpl: <b>
        PsiElement(CHARACTER)('b')
      RegExpCharImpl: <c>
        PsiElement(CHARACTER)('c')
      RegExpClassImpl: <[\>
        PsiElement(CLASS_BEGIN)('[')
        RegExpCharImpl: <\>
          PsiElement(INVALID_CHARACTER_ESCAPE_TOKEN)('\')
        PsiErrorElement:Unclosed character class
          <empty list>