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by Artemidoros 5877 days ago
Your friend might be wasting a lot of effort (apart from his personal learning experience), as Phil Bagwell is working on Scala's collection library.
2 comments
arohner 5877 days ago
For context to "outsiders": Bagwell wrote the papers that the Clojure datastructures are based on.
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KirinDave 5877 days ago
“A lot of effort?”

Wrapping the PersistentMaps took like less than 200 lines of code: http://github.com/codahale/yoink

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Artemidoros 5877 days ago
Yes, 'a lot' is quite relative. :-)

From my point of view 200 LoC giving me something I already have is a lot. From the point of view of your friend 200 LoC might be a very small price to pay for a good learning experience.

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codahale 5877 days ago
I invite you to benchmark the two.

I'm also slightly confused as to why you think reusing stable, proven, and reviewed data structure implementations is a "good learning experience" as opposed to being SOP.

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Artemidoros 5877 days ago
scala.collection.immutable is/will not be stable, proven and reviewed?
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codahale 5876 days ago
The hash array mapped trie was committed to trunk 3 months ago and was first released in 2.8.0.RC1 (which no one uses due to various bugs) and is now available in 2.8.0.RC2 (which very few people are using due to binary incompatibility).

In contrast, Clojure's PersistentHashMap dates back to 2007 and was in both the 1.0 and 1.1.0 releases.

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Artemidoros 5876 days ago
Is it unreasonable to expect that Scala's persistent collections will work comparably to Closure's when 2.8 final is released?
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KirinDave 5877 days ago
The back of your hand is going to get sore with all those compliments.
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Artemidoros 5876 days ago
I did not have the intention of backhanding you or your friend. If my post had the appearance of doing so, I apologize.

I just wanted to point out the (for me at least) non obvious fact that the mind behind the theory of Clojure's persistent datastructures is working on Scala's collection library and that Scala's hash maps are already backed by hash tries - http://www.scala-lang.org/archives/downloads/distrib/files/n...

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KirinDave 5876 days ago
Good for Scala. When it's ready, people can use that. Until then, there are interim solutions.

And it's pretty neat to see a scala proponent call a scala project a "waste of time." Way to represent for your community, bro.

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