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Comment by makecheck | Hacker News Reader

The nice thing about Python is that aliasing is pretty easy to shorten tedious statements (while not being magical). If I had to write tons of those in code, I might say:

  D = decimal.Decimal
  x = D("1.2345")

Also (at least this was once true) by doing so you save Python from a dictionary lookup after the dot "." each time.

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Or from decimal import Decimal as D

You could, but it's very unobvious. Unless you had it as a clear convention across the code base I'd imagine it would just lead to a lot of confusion.

Wait. This is extremely common to do in Python. If it really led to lots of confusion, I don't think it'd be that common.

What's common isn't necessarily a good practice to follow - https://google.github.io/styleguide/pyguide.html#Imports

By importing a function and assigning a 1 char alias to it, the readability of the code is impacted.

I'm a bit confused by your comment. From your link: > Use from x import y as z ... if y is an inconveniently long name.

"import ... as" is both common and per Google's style guide a good practice to follow in this scenario.

No, the Style Guide says "use imports for packages and modules only", which (alias or not) rules out importing single functions.

You're right. I wouldn't import a function as a single letter module if I was only using it once or twice, but I do think there's value in some cases. decimal.Decimal("1.2345") or even d.Decimal("1.2345") can be cluttering.

Going by the guide, you would do 'import pprint; pprint.pprint("foo")'...which, at least in my experience, I've never seen. It's always "from pprint import pprint" or "from pprint import pprint as pp" It could be that I work with slobs.

I don't think having a different view on the relative value of conciseness vs. visible name spacing than is at play in the Google Python style guide makes you a slob.

You find "decimal" to be an inconveniently long name? In my experience "import...as" is reserved for things like PowerIterationClustering and the like. The overriding principle is to always choose readability over succinctness.

Depends how often it's used. If you're just calling it once I wouldn't bother, but I was going off of makecheck's comment of, "if I had to write tons of those in code." I misread the style guide linked, I do find decimal.Decimal("12.34567") inconveniently long--but I generally don't mind inconveniently long names for increased intelligibility and the IDE does most of the heavy lifting. I don't often use "as" it's usually to increase the readability.

Similarly, I often see "from pprint import pprint as pp"

While I haven't used it with something as rarely used as Decimal, I almost always alias numpy and tensorflow to np and tf respectively. I find it cleans up the code drastically.

Those are common conventions for those particular libraries though.

Maybe so, but more obvious than what the grandparent wrote.

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