Software Craftsman Atlanta Meetup Recap

Enjoyed my first meeting of Software Craftsman Atlanta at Greater Sum. I was a great experience to step into a group of varying levels of talent that wanted to work together on making things. “As always this is probably more for my sanity than your learning”.

Software Craftsman has a great format starting with “Lightning Talks” where anyone can get up and speak for a few minutes. It was a quiet room so I jumped up and spoke about ES6 Generators which are functions that allow for the pausing and restarting. They can be really valuable in controlling the flow of data.

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I was impressed by a few coding camp students who stepped out after 8 hours of class to attend. That says a lot about them.

We spent a few minutes digging into Clean Code by Robert C. Martin, they are covering a few chapters every month. It was a good conversation given the diverse language experiences of the groups (C#, Java, JavaScript, Ruby, Clojure) especially since the talk was on Concurrency which is a less understood concept in JavaScript. Here is a LINK to Kyle Simpson’s 3 Part series on it.

For the last hour we grouped up and did mob coding on the “BOWLING” kata. A big focus with this group is on Test Driven Development (TDD), which I have not done much of but as I do I can really see the value. I enjoyed it and I am going to continue to refactor my code and attempt to apply the idea to different design patterns as practice.

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Software Craftsman Atlanta Meetup Recap

JAVASCRIPT FUNCTIONS HOIST AT SAME LEVEL?

I’m enjoying the work that Kyle Simpson has done on understanding how the compiler (yes, he says JavaScript is a compiled language not an interpreted one) declares and hoists functions and values. A cool thing about it is that functions do not hoist in a stacked way, they hoist in a mutual way and he has an awesome example to prove it. “As always this is more for my sanity than yours”.

I have a huge goal of understanding JavaScript better. Digging deep into it is really helping my confidence and understanding of larger concepts. “Every thing below is my interpretation and you should do your own research”.

First there is a difference between function declarations (statements) and function expressions.

function b(){}   //function DECLARATION(statement)

var a = function(){}   //the left is a variable DECLARATION, the right is a function EXPRESSION

The code below is a great example the start with. Hoisting is really something we made up to explain a complex feature that the Engine executes. But, at the running of this code the engine will run all the way through the code identifying all DECLARATIONS and assign them positions in memory then, during execution the engine will run through the code line by line assigning values.

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So the above code basically (how we see it) runs like below:

Screen Shot 2016-05-25 at 2.46.57 PM

“Var a” and “var b” are both declared and set with a value of undefined (yes it’s a value). Then the code will run line by line. Above you can see that “a” is set to “b” while “b = undefined”, then “b” is set to “2”, “a” when logged is still “undefined”.

Now, function declarations (some call them statements) are hoisted ABOVE variables when declared and function expressions are not hoisted. Simpson talks about the LEFT of EQUALS is Declared at compile and the RIGHT is Assigned at execution.

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Above code basically hoists (how we see it) like the code below.

Screen Shot 2016-05-25 at 4.10.03 PM

From what we know about how variables hoist we would think that functions would hoist in the same manner. A function declaration (statement) hoisted below the above function declaration (statement) should not be able to be called.

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Simpson argues that if this language was a truly interpreted language that read line for line then the above would not work. Functions declarations (statements) are actually hoisted at a “MUTUAL LEVEL”.

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He proves this with a Computer Science concept called Mutual Recursion, where multiple functions are calling each other. PS. sorry if you read the link and now your brain hurts!

Here is his example (the code works fine):

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The answer should be 39. I worked the problem out free hand below.

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a() is checking for completion (foo > 20) and returns a call to b() while adding +2 to foo.

b() is returning a call to c() and adding + 1 to a stack that will grow due to closure

c() is calling a() and passing foo * 2

after 3 rounds a checks that foo(36) > 20 and returns foo which in turn will grab the b stack (3) “that b stack is sitting in memory I think due to closure, I need to do more research”

a(36) + b(3) = 39

 

*Side note: this might also explain why primitive variables passing to other variables are copies. eg “a = 5;”, “b = a”, “a = 1”, “log b & log a”, “a=1”, “b = 5”. Where as “function a () {return ‘car’}”, “var b = a;”– these are pointing at the same function, so if function a is changed then function b is changed. I need to do more digging.

Kyle talks about this compiler in much more detail, talking about how the compiler looks at Left Hand Statements vs Right Hand Statements among other concepts. It’s really good stuff and he has a course on Plural Sight which goes into a lot of depth.

JAVASCRIPT FUNCTIONS HOIST AT SAME LEVEL?

Notes From ReactATL Meetup

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Great time tonight at ReactATL Meetup hosted by Andrew Smith and Taggart Bowen-Gaddy. It was an open format where people could come in with questions or examples and just talk code. “Like always this is more for my sanity than yours”.

Andrew, talked about dealing with Redux and components the problems that come from multiple components using the same state. He talked about using Reselect and NuclearJS to deal with this with the creation of selectors. I have to be honest I need to dig into it to understand it but, both seem to have good documentation (I’ll add to the list of 45 other libraries I need to look at).

Taggart talked about FalcorJS, which is Netflix’s answer to data management between the server and client built for React.  He showed a proof of concept he has been working on for his team. It is basically a mutable  JSON file. You basically send out a call for a defined box and the server will work to fetch that data and manipulate what is in the box. This box can cache to keep from having to continuously update the whole file. I thought about the idea of “closures” for JSON data transfers (note: I could be completely wrong about this). He also talked in Redux about not using a true Action Generator file and instead holding the Actions in the Components to keep from experiencing errors due to poorly called or worded dispatches.

I showed off some simple React examples I have run up. They were good examples for the guys who had not seen Redux. You can access them below and compared the differences in main components between regular React and React Redux:

Weather App

Timer App,

Todo App w/ Redux (note: I am adding authentication and moving this over to Firebase so if you notice a functionality issue, sorry)

PS. I think Google’s Firebase is VOODOO. You can find the source code for these projects on my GitHub.

Notes From ReactATL Meetup

Braving the DOM

I screwed up……. “As always this blog is more for me than you”. I get that lots of people can be great front-end devs and never really get outside of the frameworks and libraries that are so popular. I am not that guy, I am never confident unless I understand how things work. I’ve been digging through Anthony Alicea and Kyle Simpsons works on JavaSript and now I am starting to tackle the DOM with Cody Lindley’s DOM Enlightenment.

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DOM Enlightenment

Cody Lindley (so the reviews say) writes the best book focused on understanding the front end environment. It’s intimidating taking my understanding of JavaScript (it’s getting way deeper) and applying it to the manipulation of the DOM. Many people will never get outside of jQuery etc… but as I’ve dug into jQuery’s source code (which is actually funnish) I am sold of better understanding how to build with the clay of the DOM.

Braving the DOM

Take Aways From Atlanta NodeJS Meetup

Awesome time at my first NodeJS Atlanta Meetup. I was a much smaller group than they usually have so it allowed a lot of young developers to ask questions. Having only ran up simple NodeJS servers so far it was a great experience to hear from some who sit on the backend all the time. Here are a couple takeaways:

“As always this is for my sanity, not yours”

ARE PROMISES CURRIED FUNCTIONS?

I dig Promises, they make things simple to understand. If something resolves .then() do this next thing. New work on Promises and ES6 HERE (not sure I understand it all).

Function currying is creating a function that takes # variables and creating a copy of that function that takes a different # of variables:

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MY TAKE IS YES?…….MAYBE?

Yes, if we look at both currying and promises as guaranteeing something to be passed to the next function from a function that has finished executing (Closure).

 

HOW TO LAND A JOB DISCUSSION

Michael Gokey, Industry Veteran-

Fix a problem for me. Show me you can fix a problem I have in the interview. When you get in the door keep doing that for EVERYONE! The Business Dev guy had a $2 Million presentation on the line and his computer went down. Rather than shrug it off, I set him up on my computer. It took me off line for 3 hours, but I fixed a problem, helped him and I in the long run.

Also, there is a huge separation in opinions on the value of GitHUB with younger developers and hiring managers focusing on it and older developers not feeling that it has much value.

 

LEARNING FROM THE VETS

I enjoyed connecting afterwards with long time developers. Couple things on the list to check out:

Codality

Bower

Google Style Guide for JavaScript

Idiomatic JavaScript

 

Take Aways From Atlanta NodeJS Meetup

I’m In An Abusive Relationship: With Code Wars

Code Wars: “Hey Ryan, come here take this challenge…… you know you want to”.

Me: “You ruined my life! I hate you! But, okay, one more time.”

I am in an abusive relationship, with Code Wars. Don’t get me wrong, I love it. But, as a younger developer it can be exhilarating or depressing experience. If you don’t know Code Wars is a website that allows people to tackle different coding challenges. I right now am a Level 5 hopefully soon to be a Level 4 (Level 1 is the best).

Some of the challenges are how might I say this? “Quite absurd” Here is an example:

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The amount of things I need to google in the picture above are astounding!

Though, completing these challenges is exhilarating, as a young programmer these can also be a bit confidence rabbit hole (imposter syndrome, no doubt), particularly when you have spent HOURS on a solution and compare it to others.

(node the code above, just an example)

Me: “4 hours, 37 lines of code”

Arsky8867: “2 lines of code, using .map() .filter() a ternary operator and a regular expression!”

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Seriously? What is this? This is voodoo?….. and I admire it.

“Unreadable code = bad code” yes, I’ve heard the pitch but as a newer coder and after taking hours of time I find this both frustrating and exciting.

I want more! More pain, please!

Ergo….. I am in an abusive relationship…. with Code Wars.

 

I’m In An Abusive Relationship: With Code Wars

Teach It So That You Understand It

It’s hard to understand new concepts let alone create with them. As a new developer there is always the feeling of drowning in information. I’ve been working on gaining a better understanding of concepts by teaching them to others.

Blooms Taxonomy tries to explain the different levels of comprehension that we have when dealing with a concept. It works really well when you think about developers, the best are working in open source creating, evaluating and analyzing.

bloomtaxonomy

Taking your understanding of a concept and teaching others is a great way of moving up this pyramid:

  1. Can you identify, recognize and explain this to others?
  2. Can you apply and demonstrate?
  3. Can you compare and contrast (callbacks vs promises?).

This is why Paired Coding and effective Mentorships work so well. It’s people working on this practice. Sometimes we find out we can CREATE but cannot EXPLAIN. When this happens we need to realize our gaps and work on them (I have plenty more gaps on the top of this pyramid).

APPLICATION

Recently I have been jumping on Free Code Camps Gitter and offering to host Google Hangout lessons on concepts I am working on. The other night I showed people how to set up their first Nodejs server so they could work in a local environment. This week I am going to jump on and talk about “call backs” or maybe explain the “execution stack”. This isn’t about me being an expert, it’s about me demonstrating an understanding of concepts that will allow me to challenge myself through application and analysis.

This can help all of us (newer, new and old) developers by making us work through these phases of Blooms Taxonomy for true mastery.

Teach It So That You Understand It