json::value(const json_pointer&, ValueType) requires exceptions to return the default value.

[rupertsteel]

json::value(const json_pointer&, ValueType) is defined as:

template<class ValueType, typename std::enable_if<
             std::is_convertible<basic_json_t, ValueType>::value, int>::type = 0>
ValueType value(const json_pointer& ptr, ValueType default_value) const
{
    // at only works for objects
    if (is_object())
    {
        // if pointer resolves a value, return it or use default value
        JSON_TRY
        {
            return ptr.get_checked(this);
        }
        JSON_CATCH (std::out_of_range&)
        {
            return default_value;
        }
    }

    JSON_THROW(std::domain_error("cannot use value() with " + type_name()));
}

If exceptions are disabled, JSON_TRY turns into if (true) and JSON_CATCH turns into if (false), this means that the default value will never be returned if exceptions are turned off.

[nlohmann]

You are right - the function value currently relies on exceptions. I currently only see copying a lot of the implementation of get_checked() into the function to fix this.

[nlohmann]

I think the easiest would be to remove the function when exceptions are turned off.

[TurpentineDistillery]

I'm seeing that the code in certain places still uses throw instead of THROW - was that intentional or an oversight?

[nlohmann]

@TurpentineDistillery This is an oversight. Thanks for noting!!

[nlohmann]

Replaced the throw calls.

[nlohmann]

Realizing this function without exceptions would mean doubling the code.