# boyer-moore search gives the position of the first occurrence of a pattern starting at position `from`
	redef fun search_index_in(s, from)
	do
		assert from >= 0
		var n = s.length
		var m = _length

		var j = from
		while j < n - m + 1 do
			var i = m - 1 # Cursor in the pattern
			while i >= 0 and _motif[i] == s[i + j] do i -= 1
			if i < 0 then
				return j
			else
				var gs = _gs[i] # Good shift
				var bc = bc(s[i+j]) - m + 1 + i # Bad char
				# Both are true, do move to the best
				if gs > bc then
					j += gs
				else
					j += bc
				end
			end
		end
		return -1 # found nothing
	end

	# require: not optimize_has
	#
	#     assert "l".to_re.search_index_in("hello world", 0) == 2
	#     assert "el+o".to_re.search_index_in("hello world", 0) == 1
	#     assert "l+".to_re.search_index_in("hello world", 3) == 3
	#     assert "z".to_re.search_index_in("hello world", 0) == -1
	redef fun search_index_in(text, from)
	do
		assert not optimize_has

		var comp_res = compile
		assert comp_res == null else "Regex compilation failed with: {comp_res.message}\n".output

		var native = native
		assert native != null

		# Actually execute
		text = text.to_s
		var cstr = text.substring_from(from).to_cstring
		var eflags = gather_eflags
		var match = self.native_match

		var res = native.regexec(cstr, 1, match, eflags)

		# Found one?
		if res == 0 then return match.rm_so + from

		# No more match?
		if res.is_nomatch then return -1

		# Error, should be out of memory but we cover any possible error anyway
		var error_str = get_error(res)
		"Regex search failed with: {error_str}\n".output
		abort
	end

	redef fun search_index_in(s, from)
	do
		var stop = s.length
		while from < stop do
			if s[from] == self then return from
			from += 1
		end
		return -1
	end

	redef fun search_index_in(s, from)
	do
		assert from >= 0
		var stop = s.length - length + 1
		while from < stop do
			var i = length - 1
			while i >= 0 and self[i] == s[i + from] do i -= 1
			# Test if we found
			if i < 0 then return from
			# Not found so try next one
			from += 1
		end
		return -1
	end