[JSON][review] Should there be an equality operator/function?

From: Hadriel Kaplan (hadrielk_at_[hidden])
Date: 2020-09-12 00:21:20

Howdy,
I’ve been testing Boost.JSON in preparation for writing a review, and one thing that I found surprising might be better discussed in a separate thread, so here goes…

There’s currently no comparison function or operator to compare one json::value with another.

While I appreciate that a deep comparison isn’t cheap - it’s O(N) for the average case but O(N^2) in the worst case I believe - I still think it’ something a JSON-based container value type should have out-of-the-box. It’s something other popular JSON libraries offer; usually with equality operators, although a named function would be ok too if that was required instead.

I hit the lack of it almost immediately, since test code/assertions frequently check equality. I’m not sure how frequently it’s used for run-time code in general, however.

-hadriel