Often when I am using the command line in a terminal on Linux I need to go back more than one directory. Usually you use the command
cd ..
Which takes you back one level in a directory. For example if you are in /var/www/http and you type cd .. you will be in directory /var/www/.
But what if you are super deep in the directory and need to get back to www directory. Say you are in /var/www/http/website/public and you want to get back to /var/www/http you can either type: cd .. ( inside /var/www/http/website/ )
cd .. (inside /var/www/http/ now )
But you can type the following and get all the way back to the /www/http/ directory in one line cd ../..
That line will take you back two directories. If you need to go further back just continue adding ../..
While trying to figure out how to do this I found lots of bad info, info that lead to nothing but issues and bugs. I have stay so busy and do so many things I can never remember how to do anything. That is basically why this ENTIRE blog exists, my shit memory.
One of the oddest things I encountered when starting to learn Scala was seeing variables called values instead of variables.
When I first started reading the docs I saw a list of values of the classes, traits etc. I kept wondering WTF is a value why not call it a variable like every other language.
So for a while I just thought the Scala community just referred to all class variables as values.
Then I was reading the docs some more, I found this page. It has this one easy to miss line that answers the question why are vals called values instead of variables.
The second sentence below the difference between Val and Var
“Because val fields can’t vary, some people refer to them as values rather than variables.”
And that is the answer. In the Scala API documentation most classes/objects you see has a list of values defined with val.
I suppose the class variables are defined this way so that you don’t accidentally mutate them or change them.
I am still not sure why methods are called members yet, when I figure that out maybe I’ll write about it.
I found this link somehow. This guy has all kinds of interesting information about databases, programming and technology in general . https://aphyr.com/tags/jepsen
I am all over in the tech. I have quite a few inventions I am working on. I stay busy learning about tech all day everyday and all it does is give me more and more ideas. One day I’ll catch a break and get some money and start inventing away.
Therapeutic Ultrasound with Piezo Components
This is a seriously interesting article about the medical uses for piezo generated waves. Things such as tumor destruction, targeted medicine release and Intravascular Lithotripsy ( plaque removal in the arteries ) I was just thinking about how we need a way to remove plaque to help reduce blood pressure and extend life the other day. I think about an insane amount of things all the time, the more complex the better.
This has some interesting information on the subject. I got into the piezo devices because I designed a mining device that has 0 ZERO mechanical parts. I want to build a mining device because I want to get off earth and live inside an asteroid, a ship inside an asteroid to be highly stealthy and hide from other life. There is other life, Earth is roughly 1/4 the age of the universe, it has had billions of years to find us and hide from us. That is a series of articles though. I even know why aliens probe buttholes and E.T’s finger glows. LOL
