Comments on: Various Small Python Helpers

By: Aldrin Martoq - Technical Weblog » Blog Archive » The quest for the perfect python enum/constant declaration, Part 2

Tue, 23 Dec 2008 01:02:57 +0000

[...] language. One hint for this is the many enum-like solutions you can find around the net. Some are simple and clean, but none provides all the features I [...]

By: lorg

lorg — Fri, 14 Mar 2008 12:50:44 +0000

1. You are correct. Using %x is more elegant, and will work in Python 3.
2. You are correct on this one as well. In fact, my implementation of head might cause a potential bug. This is because zip (and izip) leave long iterators in an uncertain state, by taking more elements than they should.

By: Erez

Erez — Thu, 13 Mar 2008 18:05:12 +0000

Hi, two suggestions:
1) Replace hex(self)[2:-1] with ‘%x’%self. It’s prettier.
Also, the ‘L’ postfix gets abandoned in Python 3.0 .

2) Your ‘head’ function is just a special case of ‘itertools.islice’ .

By: lorg

lorg — Sun, 09 Mar 2008 22:53:26 +0000

Yoni: You misunderstood my intent. Head takes the first num_items from iterable.
I’m piggy-backing on zip’s behavior. zip always takes the shorter of the input sequences.
It also works for infinite sequences (such as itertools.count()).

Maybe I should have used itertools.izip instead though, to avoid generating the num_items of iterable at once.

And thanks!

By: Yoni

Yoni — Sun, 09 Mar 2008 22:16:40 +0000

Neat @ first two.

The last one isn’t missing (unless I misunderstood your intent): “enumerate” is a built-in since Python 2.4, I believe.