Why JSON Doesn’t Have Comments
Douglas Crockford (via Dave Dribin):
First, comments turned out to not be very useful.
Second, comments were the most difficult feature to support in JSON parsers. By removing comments, support for JSON in other languages became much easier.
Third, removing comments aligns JSON more closely with YAML, allowing YAML to become a JSON superset. Generally, standards tend to splinter. It is interesting to see these two merging.
Fourth, I saw examples of comments used to carry information, with an expectation that applications would have to have custom comment parsers and generators. That was not a pattern that I wanted to encourage.
Douglas Crockford (via Dave Dribin):
I removed comments from JSON because I saw people were using them to hold parsing directives, a practice which would have destroyed interoperability. I know that the lack of comments makes some people sad, but it shouldn’t.
Update (2015-08-01): Hacker News comments.