TIL, 2018-01-02, Back to Elixir

Shell scripts, you can put the commands into their own lines.
I’m revisiting
Ruby contracts: Reference
Removing “\n”: You need to use “\n” not ‘\n’ in your gsub. The different quote marks behave differently. Reference

Ruby class vs Elixir module

Ruby class. Data: instance of the class hold state in instance variables, and behavior: methods on the class alter state.
Elixir modules. Data: an immutable data structure, and behavior: the module’s functions define state transformations, often taking the struct as input.
Problem: if you change something, and call a method on it, it can break.
- In Elixir, there is no need to keep track of state because you just create a new object for this.
- Same with behavior. If you are “modifying something”, in Elixir, you are forced to create a new object with that “modified something”.

Erlang is strong in parallelism but not so much in number crunching power.
The GPU is good at getting loaded up with data and crunching it all at once. Bad when you have to go to disk, network, I/O channel for data.
If you program requires heavy use of I/O channels, a better machine would be a cluster. Communication and control systems are ideal applications of Erlang because each individual processing task takes little CPU and only occasionally needs to communicate with other processing nodes.
Erlang makes parallelism easier to work with for developers.