The files in inst/include and inst/include/re2, inst/include/util, and src/ subdirectory,

    inst/include/re2:

    filtered_re2.h
    prog.h
    set.h
    unicode_groups.h
    prefilter.h
    re2.h
    stringpiece.h
    variadic_function.h
    prefilter_tree.h
    regexp.h
    unicode_casefold.h
    walker-inl.h

    inst/include/util:

    atomicops.h
    logging.h
    random.h
    test.h
    util.h
    benchmark.h
    mutex.h
    sparse_array.h
    thread.h
    valgrind.h
    flags.h
    pcre.h
    sparse_set.h
    utf.h

    src/:

    bitstate.cc
    nfa.cc
    stringpiece.cc
    compile.cc
    onepass.cc
    stringprintf.cc
    dfa.cc
    re2.cc
    parse.cc
    strutil.cc
    filtered_re2.cc
    perl_groups.cc
    tostring.cc
    hash.cc
    regexp.cc
    prefilter.cc
    unicode_casefold.cc
    logging.cc
    rune.cc
    prefilter_tree.cc
    unicode_groups.cc
    set.cc
    prog.cc
    valgrind.cc
    mimics_pcre.cc
    simplify.cc

were originally written by:

    RE2 developers

and modified by Qin Wenfeng.

The files in inst/include,
	
	optional.hpp

were originally written by:

	Andrzej Krzemienski.

The files in inst/htmlwidgets/lib ,
	
	main.js
	main.css

were originally written by:

	 Jeffrey Avallone.

and modified by Qin Wenfeng.

Other part of this package is written by Qin Wenfeng.
