REGEXP_FILE
  RegExpPatternImpl: <[^\]]>
    RegExpBranchImpl: <[^\]]>
      RegExpClassImpl: <[^\]]>
        PsiElement(CLASS_BEGIN)('[')
        PsiElement(CARET)('^')
        RegExpCharImpl: <\]>
          PsiElement(REDUNDANT_ESCAPE)('\]')
        PsiElement(CLASS_END)(']')