Set data structures about janet HOT 4 CLOSED

Probably not as a core data structure, although it would be possible to add one as an abstract type. Abstract types cannot emulate all of the features of built in types right now, such as length, hash, equality, call, and print methods, but I would consider adding some of these features to the abstract type interface.

All that said, I think there is benefit to using a few core data structures - enough for many use cases, but few enough that making generic functions is easy.

You could of course also do something like:

(defn make-set 
  [& els]
  (let [tab @{}]
    (each el els (put tab el true))
    (table/to-struct tab)))

(make-set :a :b :c)
# -> {:c true :a true :b true}

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oops, I don't know about abstract types, what do we already have for now?

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Abstract types are native C types, you would have to write your own in C. The current abstract types in the core are files and typed arrays, and there are some others in external packages.

I would recommend using tables for sets, though.

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The package index references janet-set, an implementation of set types in Janet.

Janet-set uses janet-abstract (https://github/mikebeller/janet-abstract.git) in order to create a new abstract type directly in Janet. This allows us to "hook" into get/put/tostring/next so that our sets will support length calls, normal Janet iteration, and print out in a sensible way.

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