REGEXP_FILE
  RegExpPatternImpl: <a\(*b>
    RegExpBranchImpl: <a\(*b>
      RegExpCharImpl: <a>
        PsiElement(CHARACTER)('a')
      RegExpClosureImpl: <\(*>
        RegExpCharImpl: <\(>
          PsiElement(ESC_CHARACTER)('\(')
        RegExpQuantifierImpl: <*>
          PsiElement(STAR)('*')
      RegExpCharImpl: <b>
        PsiElement(CHARACTER)('b')