From 4237b15a767fdc1adab6d4495b74b57f74cd4381 Mon Sep 17 00:00:00 2001
From: Baojun Wang <wangbj@gmail.com>
Date: Mon, 9 Sep 2019 12:55:57 -0400
Subject: [PATCH] allow empty string to be valid positional arguments

---
 include/cxxopts.hpp | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/include/cxxopts.hpp b/include/cxxopts.hpp
index ed3c6a2..e932547 100644
--- a/include/cxxopts.hpp
+++ b/include/cxxopts.hpp
@@ -743,6 +743,12 @@ namespace cxxopts
     void
     parse_value(const std::string& text, std::vector<T>& value)
     {
+      if (text.empty()) {
+	T v;
+	parse_value(text, v);
+	value.emplace_back(std::move(v));
+	return;
+      }
       std::stringstream in(text);
       std::string token;
       while(in.eof() == false && std::getline(in, token, CXXOPTS_VECTOR_DELIMITER)) {