I tried some change to dump() for [1,2,3...]

[taodm]

function dump under pretty print maybe not good enough，it will use too many lines.
I tried some change to dump(),maybe can be accepted.

when json j is [1,2,3...],use j.dump(4),get:
[
1,
2,
3,
...
]
I want get [1,2,3..] in one line
so, I changed here:
void dump(const BasicJsonType& val, const bool pretty_print,
const bool ensure_ascii,
const unsigned int indent_step,
const unsigned int current_indent = 0)
...
case value_t::array:
{
if (val.m_value.array->empty())
{
o->write_characters("[]", 2);
return;
}

            if (pretty_print)
            {
                auto subitem_type = val.m_value.array->cbegin()->m_type;
                bool full_pretty_print = subitem_type == value_t::array  ||
                                         subitem_type == value_t::object ||
                                         std::any_of(val.m_value.array->cbegin(), val.m_value.array->cend(),
                                                     [subitem_type](auto & subItem){return subItem.m_type != subitem_type;});

                size_t   elements_per_line  =  (subitem_type == value_t::string) ? 5 : 10;
                bool     more_than_one_line =  val.m_value.array->size() > elements_per_line;

                o->write_character('[');

                // variable to hold indentation for recursive calls
                const auto new_indent = current_indent + indent_step;
                if (JSON_UNLIKELY(indent_string.size() < new_indent))
                {
                    indent_string.resize(indent_string.size() * 2, ' ');
                }

                // first n-1 elements
                size_t element_count = 0;
                for (auto i = val.m_value.array->cbegin();
                        i != val.m_value.array->cend() - 1; ++i)
                {
                    if (full_pretty_print || (more_than_one_line && ((element_count++ % elements_per_line) == 0)))
                    {
                        o->write_character('\n');
                        o->write_characters(indent_string.c_str(), new_indent);
                    }

                    dump(*i, true, ensure_ascii, indent_step, new_indent);
                    o->write_character(',');
                }

                // last element
                assert(not val.m_value.array->empty());
                if (full_pretty_print || (more_than_one_line && ((element_count++ % elements_per_line) == 0)))
                {
                    o->write_character('\n');
                    o->write_characters(indent_string.c_str(), new_indent);
                }
                dump(val.m_value.array->back(), true, ensure_ascii, indent_step, new_indent);

                if (full_pretty_print || more_than_one_line)
                {
                    o->write_character('\n');
                    o->write_characters(indent_string.c_str(), current_indent);
                }
                o->write_character(']');

...
now, when json j is [[1,2,3,4,5,6,7,8,9,10,11],[1,2,3,4,5,6,7,8,9,0],[1,2,3,4,5,6,7,8,9],["1",1]],
j.dump(4) will get:
[
[
1,2,3,4,5,6,7,8,9,10,
11
],
[1,2,3,4,5,6,7,8,9,0],
[1,2,3,4,5,6,7,8,9],
[
"1",
1
]
]

[nlohmann]

In order to asses your issue, we need the following information:

• What is the issue you have?

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

• What is the expected behavior?

• And what is the actual behavior instead?

• Which compiler and operating system are you using? Is it a supported compiler?

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

• If you experience a compilation error: can you compile and run the unit tests?

[taodm]

I think function dump(4), pretty print not good enougf, it will use too many lines for arry of int.
I want print 10 int_value in one line,like
[
1,2,3,4,5,6,7,8,9,10,
11
],
It will use less lines,and we can quickly count how many elements.
I've tried change the code.
May it can be accepted?

[nlohmann]

I am not sure that such a fix is helpful for everybody, and we have no real way to support all kinds of configurations at the moment. Best would be a way to implement user-defined serializers (maybe using the SAX interface, see #2275).