Add log function for runtime types

[isaachier]

As of now, a user must use an initializer list to log key-value pairs. The problem is, this effectively disables any dynamic logging. For example, if I want to log a list of key-value pairs, I have to know this list at compile time, seeing as no STL container can be converted into an initializer list at runtime.

Here are a few ideas for a new log function overload:

using Iterator = std::vector<std::pair<string_view, Value>>::const_iterator;
virtual void Log(Iterator first, Iterator last) noexcept = 0;

or

[isaachier]

virtual void Log(const std::unordered_map<string_view, Value>& pairs) noexcept = 0;

[rnburn]

What would you think of adding an overload for something like LogRecord that's in the Go API?

You can use it to customize the timestamp of the log as well.

[isaachier]

I'd like that too. TBH, anything other than std::initializer_list is fine with me.