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Scala Collections: Why Not?

InfoQ · 43.2K views · 2014-01-29 · 45:42

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Overview

Paul Phillips, a Typesafe co-founder and prolific Scala committer, explains why he walked away from Scala. He critiques the Scala collections library and presents his own design focused on immutability, performance and correctness.

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Cited in Scala-skeptic arguments as an insider's critique, and for his alternative collections API design.

Discussed on HN; no positive recommendation is recorded in this export · HN mentions 2015–2020

Topics

Functional programmingSoftware architecture & designProgramming language design
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scalacollectionspaul phillipsapi designlanguage criticism

What people said

siwatanejo · 2020-11 · Criticism

Before choosing Scala I think you should watch this talk: [VIDEO] (note: he's not a troll, he worked 5 years with Scala)

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partycoder · 2017-04 · Criticism

I think all technologies have sharp edges somewhere, and the way to stay afloat in this business is staying alert. Testing assumptions help, be it through quick REPL experimentation or a unit test. JavaScript has some bad fame around unintuitive behavior but you can find these styles of issues in most languages. A random example: Scala. [VIDEO]

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harveywi · 2016-08 · Reference

> I don't want .Where() called on an array to return another array. I want a lazy IEnumerable<T> almost every time. Yes, good point. There is a lot of space to explore in collections API designs, and the LINQ design is just one of them that makes its own tradeoffs (e.g., only have to implement "GetEnumerator()" to get a watered-down monadic experience). Contrast that with the well-meaning but convoluted and buggy Scala collections API (very difficult for novices to create a custom collection due to CanBuildFrom and other tricky stuff). Paul Phillips came up with a pretty neat collections API [1, 2] that provides a nice feature set, including high-performance and typesafe views when you don't really want to wastefully create a temporary collection just to interact with the first 10 elements. [1] [LINK] [2] [VIDEO]

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Sources

Video by InfoQ, played through YouTube.

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