I guess mostly how the syntax works. The `$$` thing I mostly recognize as being a code block in custom functions, but I'm not sure how it works in the context of a lambda. Also, is `$value` just a special identifier for the input?

A separate question...is it possible to have tuple-valued timevectors?

The docs have a bit more on it [1]. The $$ is really just a dollar quoted string[2], you can use any sort of string in there, but dollar quoting just makes it a lot easier to read.

On your other question, not right now, but if it's something you want, file a github issue, it's something we've thought a bit about and it gets hairy pretty quickly, but also increases the power of these things dramatically. We'll probably do something with it, but it may be a little while and we may let this stuff bake for a bit first...

[1]: https://docs.timescale.com/timescaledb/latest/how-to-guides/... [2]:https://www.postgresqltutorial.com/dollar-quoted-string-cons...