The Art of Refactoring

Me

Polyglot :C, C++, Ruby, Java, Scala, JavaScript, Go, Python, etc.

Senior Software Engineer :Over 13 years of experience professionally.

Math Nerd :Discrete Math (Graph Theory, Number Theory, Information Theory, Model Design, Algorithm Analysis & Design

Daniel Marvin daniel@cloudpack.io http://daniel.cloudpack.io

Amateur Wormhole Theorist :The speed of light just isn’t fast enough.

http://capterra.com

In Computer Science, as we evaluate and analyze algorithms, we consistently ask ourselves, “Can we do better?”

We will ask ourselves a similar question in regards to refactoring.

But what is our goal? Why does it even matter?

Can We Do Better?

What’s the Point?

While huge improvements have been made with tools for solving problems, we want to ensure we get the most out of our code.

We want to make sure that others can read and understand our code — including others like our abstract self — days, weeks, or months after having written the code.

We want to make sure that we can easily add to our code without needing to re-write massive portions.

OMG, that code is $&*#ing horrible!!!

Best PracticesWorst Practices

Many Ways

Ruby offers us numerous ways to accomplish the same tasks and this can be good or bad. !

All code is just code. !

However, somethings you don’t want to do.

Improper use of globals

Class name in class methods

One or two character variables

Unnecessary iterations

Multi-purpose methods

Things to NOT do

Classes as data structures

Object misuse

Memory abuse

Less Obvious Bad

Memory Usage

Because Ruby makes things very easy for us, it is also easy to take for granted not needing to manage memory, however when it comes to optimizing code, it is very helpful to have an understanding of the Garbage Collector, how Ruby objects function under-the-hood, and how data is moved around.

PbV or PbR? Not beer.

One important thing to know is how Ruby passes around data. !Pass-by-value : A copy is made. Pass-by-reference: The memory location is referenced. !C Ruby does a combination of both! !J Ruby does a combination of both too, however the way the JVM’s GC works is a bit different, so we’re not going to chat about that today.

value = “this is a string”

value.class #=> String

value.object_id #=> 70198768696180

printf("0x%X", (value.object_id << 1)) #=> 0x7FB0D957F6E8

MEMORY BLOCK: 0x7FB0D957F6E8

We Have Ways Of Making Objects Talk

Homework: Ruby Fiddle!!

Thanks and keep hacking!