On the other hand:
> leadingDecimalPoint: .8675309
This is just lazy. Can we discuss in depth how much time you saved by skipping the “0” in favor of lesser readability?
> andTrailing: 8675309.,
This doesn’t mean anything to me.
On the other hand:
> leadingDecimalPoint: .8675309
This is just lazy. Can we discuss in depth how much time you saved by skipping the “0” in favor of lesser readability?
> andTrailing: 8675309.,
This doesn’t mean anything to me.
On a personal level, I also don't like ending a number with a . because my brain immediately parses it as a sentence ender and it interrupts my reading flow.
It's just not wanting to keep track of more rules. If you've only ever used languages where a leading decimal point is allowed, it's a pain point to suddenly have to remember that it isn't here, and for no obviously intuitive reason.
It's about wanting to avoid unnecessary conceptual friction. Not lazy keyboard usage.
(Heck, your second example uses an extra keystroke. And it's perfectly readable to me, based on the languages I use.)
JSON5 is not.
There's something to be said for being flexible in your inputs when they are non-ambiguous. Particularly when dealing with files written by hand.
There's no virtue in imposing overly strict syntax when it serves no human purpose. That's trying to alter people to fit machines, rather than altering machines to fit people.
This seems like exactly how we ended up with YAML-and-the-kitchen-sink.
For a spec like this, things should need a better justification than that. Everything starts at -100 points. How does this feature justify the additional complexity in the spec, to the users, and to the people trying to implement this? How does it justify increasing the opportunity for creating subtly incompatible parsers?
Or, if a goal of JSON is not to be simple and interoperable, then I fail to see how it's not just YAML but 5 or 10 years behind the curve, so we may as well skip a bunch of hassle and move to YAML and start fixing the bugs we've got there rather than creating new ones here.
JSON5 is literally exactly JavaScript notation, which tons of people are familiar with. On the other hand, I don't know any programming languages that use strings without quotes or delimiters. (And of course, their existing in YAML is widely recognized as a major source of confusion.)
And in your example, there isn't parsing ambiguity but there would be change ambiguity when you alter abc (without quotes) to 123, because it changes its type.
I'm not aware of any change-ambiguity situations in JavaScript/JSON5 like that? In Python 5 and 5. are different types, but not in JavaScript or JSON.
Trailing makes it a floating point type instead of an integer
Still… I can be required to put a zero in, read 0.3, and still think “that’s point three”.
Reference: Postel’s Law
I think Postel's law was intended to apply to alternative implementations of machine-level protocols.
That's not to say that I don't agree that it might be better if JSON implementations would allow trailing commas, which is unlikely to lead to semantic ambiguities. That's too late now though, unless a new JSON to rule them all would appear and we would all agree on that new spec.
https://datatracker.ietf.org/doc/html/draft-thomson-postel-w...
https://datatracker.ietf.org/doc/html/rfc9413
I don't think Postel's Law was necessarily a bad idea, in its time and context. However it seems to have fallen into usage as an argument-ender. This RFC is a useful antidote to that.
How could the parser see it as a string? This is not YAML and JSON5 still requires quotation marks.
Is it universally understood? I think it's a US / English thing. In my country I've never seen numbers written in this way and many people would not "parse" it mentally as 0.8675309