REGEXP_FILE
  RegExpPatternImpl: <(?idmsuxU)nice>
    RegExpBranchImpl: <(?idmsuxU)nice>
      RegExpSetOptionsImpl: <(?idmsuxU)>
        PsiElement(SET_OPTIONS)('(?')
        RegExpOptionsImpl: <idmsuxU>
          PsiElement(OPTIONS_ON)('idmsuxU')
        PsiElement(GROUP_END)(')')
      RegExpCharImpl: <n>
        PsiElement(CHARACTER)('n')
      RegExpCharImpl: <i>
        PsiElement(CHARACTER)('i')
      RegExpCharImpl: <c>
        PsiElement(CHARACTER)('c')
      RegExpCharImpl: <e>
        PsiElement(CHARACTER)('e')