Unexpected nested arrays from std::vector

[hoisunng]

Bug Report

• What is the issue you have?
  Unexpected nested arrays from std::vector

• Please describe the steps to reproduce the issue. Can you provide a small but working code example?

std::vector<int> v;
json j{v};
std::cout << j << std::endl;

• What is the expected behavior?
  cout prints: []

• And what is the actual behavior instead?
  cout prints: [[]]

• Which compiler and operating system are you using? Is it a supported compiler?
  RHEL7 with GCC 6.3.1

• Did you use a released version of the library or the version from the develop branch?
  Release Version 2.1.1

[gregmarr]

This is creating a JSON array object containing an empty array. What exactly are you trying to do here? I think you might want json j{json::value_t::array};

[nlohmann]

You need to write json j = v;. The braces will be interpreted as arrays themselves, allowing to write code like json j = {1, 2, 3, 4};.

[hoisunng]

Thanks, that works!