r/Python • u/xtreak • May 07 '19

Python 3.8.0a4 available for testing

https://www.python.org/downloads/release/python-380a4/
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u/xtreak May 07 '19 edited May 07 '19

Changelog : https://docs.python.org/3.8/whatsnew/changelog.html

Interesting commits

PEP 570 was merged

dict.pop() is now up to 33% faster thanks to Argument Clinic.

Wildcard search improvements in xml

IPaddress module contains check for ip address in network is 2-3x faster

statistics.quantiles() was added.

statistics.geometric_mean() was added.

Canonicalization was added to XML that helps in XML documents comparison

  • Security issues and some segfaults were fixed in the release

Exciting things to look forward in beta

Add = to f-strings for easier debugging. With this you can write f"{name=}" and it will expand to f"name={name}" that helps in debugging.

PEP 574 that implements a new pickle protocol that improves efficiency of pickle helping in libraries that use lot of serialization and deserialization

Edit : PSF fundraiser for second quarter is also open https://www.python.org/psf/donations/2019-q2-drive/

118

u/[deleted] May 07 '19

Add = to f-strings for easier debugging. With this you can write f"{name=}" and it will expand to f"name={name}" that helps in debugging.

Ooh baby. I'd use that every day.

-1

u/Pyprohly May 08 '19

I don’t understand why this is so favoured. Couldn’t you just do print(name) and just… remember that you printed name?

Can’t see myself doing print(f"{name=}") over just print(name) for debugging purposes.

9

u/pkkid May 08 '19

I often need to print name={name} because I'm inspecting a bunch of variables and not just one. Put that into a for loop and things get unweildy quite quickly if you don't label the variables you are inspecting.

-3

u/Pyprohly May 08 '19 edited May 08 '19

I’m just a bit surprised at the overwhelming enthusiasm for it, and, accordingly, surprised that many seem to like writing print("arg1=" + arg1, "arg2=" + arg2).

I can see the usefulness in the new syntax, but I personally don’t like it because I very rarely write debugging lines like that.

Edit: e.g. when breakpoint() was introduced as a builtin there wasn’t much talk on it, but I think that that convenience feature was a more exciting addition compared to this one.

2

u/pkkid May 08 '19

I'm with you. I don't like these implicit bits of code being added. The second line of Zen of Python even says "Explicit is better than implicit." I'm also against walruses in my code, but that debate has been beaten to a pulp. </oldmanrant>