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PEP 572: Python assignment expressions has been accepted

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317 points est | 1 comments | 03 Jul 18 08:30 UTC | HN request time: 0.212s | source
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oooooof ◴[03 Jul 18 09:00 UTC] No.17448560[source]▶
What is it? The link points to a discussion more deep than I’m willing to read.
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kibibu ◴[03 Jul 18 09:06 UTC] No.17448591[source]▶
High-level overview: it's an assignment operator that returns its value, similar to C's assignment operator.

The choice of := is to avoid accidentally using assignment where comparison is expected.

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arketyp ◴[03 Jul 18 09:38 UTC] No.17448770[source]▶
I feel the colon is unnecessary, especially considering how C deals with this. A plain '=' inside a conditional is already invalid syntax in Python.
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heavenlyblue ◴[03 Jul 18 09:42 UTC] No.17448792[source]▶
No, it's necessary.
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1. arketyp ◴[03 Jul 18 09:59 UTC] No.17448898[source]▶
How so? Syntactically, or from a pragmatic point of view?