Blog
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Python’s objects and classes — a visual guide
Python developers love to say that “everything is an object.” And indeed, when I teach Python classes, I say this several times, and many people nod in agreement, assuming that I’m merely repeating something they’ve heard before. After all, people often say that everything in Java is an object (except for the things that aren’t),…
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Registration is open for my October Webinars (about regexps and technical training)
September has been busy with work and holidays, but I’m gearing up for an exciting and busy October. Among other things, I’m giving two (free) Webinars in that month, and you can already register for them: Intermediate Regular expressions: In my previous Webinar about regular expressions, I covered the basics. In this one, we’ll go…
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Now available: My interview on “Developer on Fire” about training programmers
I was recently interviewed by Dave Rael for the “Developer on Fire” podcast. That episode has now been released, at http://developeronfire.com/Podcast/Episodes/reuven-lerner-sharing-insight. Enjoy!
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In PostgreSQL, as in life, don’t wait too long to commit
I recently helped a client with serious PostgreSQL problems. Their database is part of an application that configures and monitors large networks; each individual network node reports its status to the database every five minutes. The client was having problems with one table in particular, containing about 25,000 rows — quite small, by modern database…
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Announcing: Coaching for technical trainers
What, exactly, do I do for a living? Yes, I’m a programmer — or as I’m supposed to say nowadays, a “full-stack Web developer.” And yes, I’m a lead developer/CTO. And yes, I’m a writer, with two ebooks written (about Python and visiting China), two more on the way, and my monthly Linux Journal column…
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Want to understand Python’s comprehensions? Think in Excel or SQL.
Comprehensions are among the most useful constructs in Python. They merge the old, trusty “map” and “filter” functions into a single piece of compact, elegant syntax, allowing us to expression complex ideas in a minimum of code. Comprehensions are one of the most important tools in a Pythonista’s toolbox. And yet, I have found that…
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Why you should almost never use “is” in Python
It’s really tempting, when you first start to use Python, to use “is” rather than “==”. It’s a bit more readable, and it feels like it should just work, especially when you’re dealing with integers. In a language that uses “or” and “and” instead of “||” and “&&”, it seems logical to use “is” instead…
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Free Webinar on June 23rd: Introduction to Regular Expressions
If you’re a programmer, then you have likely heard about regular expressions (“regexps”) before. However, it’s also likely that you have tried to learn them, and have found them to be completely confusing. That’s not unusual; while regular expressions provide us with a powerful tool for analyzing text, their terse, dense, and cryptic syntax can…
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New ebook: Jewish guide to visiting China
As many people know, I’ve visited China seven times over the last three years, traveling there to give courses in Python and Ruby. I just got back from my most recent trip, and found it to be as fun and exciting as ever. You could say that I’ve gotten a bit obsessed with the country;…