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PEP 572: Python assignment expressions has been accepted

(groups.google.com)
317 points est | 2 comments | 03 Jul 18 08:30 UTC | HN request time: 0.421s | source
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amelius ◴[03 Jul 18 09:55 UTC] No.17448876[source]▶
If they add anything to Python, it should be the ability to do functional-style programming without hassle. Right now it's almost impossible to compose functions in an inline style such as used in functional programming languages. Yes, there's lambda, but it doesn't extend into multiple lines, and applying a function to a bunch of lambdas directly leads to line-width overflow. Even JavaScript has better support for functional-style programming. Perhaps Guido should spend a year writing Haskell :)
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i_do_not_agree ◴[03 Jul 18 10:16 UTC] No.17448972[source]▶
Just need something like blocks in Smalltalk. Wikipedia page on list comprehensions says Smalltalk-80 had list comprehensions and that was ~ 40 years ago.

Smalltalk also uses ":=" for assignment and "=" for comparison. In Pharo, VA and Dolphin at least does what this Python proposal does - return the value of the last expression.

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1. yxhuvud ◴[03 Jul 18 10:57 UTC] No.17449121[source]▶
Ain't going to happen. Python used to have lambdas, but removed all but the one-line variety.

The problem is that if you add blocks, then half of the added syntactic features the last decade is redundant as a block version would simply solve the problem a better. Which would create a lot of dead design, and that makes it a bad solution.

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2. pseudalopex ◴[03 Jul 18 13:46 UTC] No.17450115[source]▶
When did Python have multi-line lambdas?

Are you maybe conflating blocks with chained iterator operations? Adding blocks to Python's current functional syntax would be pretty ugly. "foo.filter(bar).map(baz)" is nice even if you can only use named functions.