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Did you know that you can replace grep and sed by perl -pe and have the full power of Perl regexs?

Examples:

Imagine you have a file with comma-separated Odoo module names and you want to extract all those that:

1. Are unrelated to payment.
2. Are from any localization except the Spanish one.

Using only grep or sed is very complicated because they don’t support negative lookaheads. However, with Perl it’s “very” easy:

Copier 6 has finally arrived! I’ll tell you what’s new.

You may also be thinking about volunteering to maintain an open source project. I’ll tell you what this experience has been like, in case it helps you to decide.

What’s new

I refactored the whole core of the program. Now it is much more maintainable. Thanks to the fact that there were so many tests, I could check that everything still works fine.

“How to install the application _______?”

I’m sure you’ve asked yourself. If you use GNU/Linux, the usual answer is: by installing a software package.

But… there are many package formats. How do you know which one is best?

Let me tell you.

System packages

I say “system” because, by installing a package in this format, what we are really doing is allowing a new software component to become part of our operating system.

Sometimes you may have a webcam that shows flickering.

How to solve it?

In my case, I have a Logitech C920 HD Pro and I was having this problem.

Why it happens

Usually it is because the camera is working at 60 Hz and the monitor at 50, or vice versa.

How to solve it in Windows

For my particular camera, it was simple:

1. download and install the Camera Settings application.
2. Open it.
3. Set the camera’s refresh rate to match that of the monitor.

How to solve it on Linux

On Linux it is also easy to do if you install the gtk-v4l package. If you are on Fedora 35:

I’ve been interviewed in Podcast.__init__ talking about Copier.

Listen to the interview.

Having a Windows virtual machine in Linux has a lot of utilities:

1. If you’re testing Linux for the first time, it can help you “unhook yourself” from Windows little by little. You know you have Windows there, and that placebo gives you the necessary courage to test this little weird new world that is Linux.
2. You’re a developer and you want to see how your apps or services work on Windows.
3. You need to use one app that has no native Linux alternative and that you cannot run with Wine.
4. You need to use one app that is only available through Windows app store.

It turns out getting it is way easier than what you imagine:

I hate negative booleans.

If any time, for any reason, you need to use a boolean variable (very common), please always think in positive.

You don’t know how many brain cells I have wasted interpreting code like this:

# Declare variable
no_update = True

# Use variable
if not no_update:
  do_something()

I mean… why not just write it like this?

# Declare variable
update = False

# Use variable
if update:
  do_something()

And time and again I keep on seeing that pattern… Seriously, always be positive please. And if you need to negate it, then just put a not operator in front of it, that’s why they exist for!

What to do when you find this 💩 in the terminal?

➤ sudo apt-get remove linux-image-generic
Reading package lists... Done
Building dependency tree
Reading state information... Done
You might want to run 'apt-get -f install' to correct these:
The following packages have unmet dependencies:
 linux-generic : Depends: linux-image-generic (= 4.4.0.143.151) but it is not going to be installed
 linux-modules-extra-4.4.0-143-generic : Depends: linux-image-4.4.0-143-generic but it is not going to be installed o
                                                  linux-image-unsigned-4.4.0-143-generic but it is not going to be installed
 linux-signed-image-generic : Depends: linux-image-generic but it is not going to be installed
E: Unmet dependencies. Try 'apt-get -f install' with no packages (or specify a solution).

It’s a little hard, but let’s go…

Something completely unnecessary but essential at the same time:

To install it:

• Page to install the extension.
• Source code.

It doesn’t work as good as the old Compiz, but it’s better than nothing!

Well, well… ok… let’s get real… Yeoman and Cookiecutter are not dead, it’s just that I wanted a catchy headline. 😁

What I mean is that suddenly a new competitor has emerged with lots of advantages, and it’s going to give them a good fight…

If you’re reading this, I guess you already know these tools, but just in case:

What are Yeoman and Cookiecutter?

Cookiecutter is a generator. Actually, until now, it’s the main referent in Python, and one of the most importants in any language.