sqe boston - when code cries

@cory_foy [email protected]

When Code Cries

Cory Foy@cory_foy

[email protected]://www.coryfoy.com

1Thursday, November 14, 13

Reading from Timeless Way. Then: All of us here are technologists in some way. We desire to build things that people will use. Living software. But if you look at our industry, the fruit of our labors is not living software. The majority of software out there has a common attribute. It is:

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http://www.8thlight.com



Bad Code


Bad Code is the bane of the software industry. Why is it that, over time, code becomes harder and harder to work with - and how can we prevent ours from ending up with the same fate? To answer that, perhaps we should start with identifying what quality code is. So, is this quality code?




Is this quality code?


Why do we like Easy to Change code? Because it is a lower cognitive burden. Because writing code is hard enough, as we’ll see.




ContextReduced

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Cognitively Undemanding

Cognitively Demanding

Where we want our software

Modifying Software we wrote

Modifying Software we didn’t write


We want code that is in the upper right quadrant. But, if we’re lucky to be modifying our own code, it’s in the lower left. Worse case, we don’t even have the context, so it’s in the lower right. Now, if we have tests, that helps increase the context. But when we don’t, we can end up with code that looks like



@cory_foy [email protected], November 14, 13

Code that isn’t a joy. That is anti-joy. Code which is frustrating to be around. This is not code that is alive - this is code which has problems. And these problems - we tend to name them something. When we see something not right in code, what do we say?




Code Smells


Right - “Smelly Code”. But what I’d like to do today is reframe the discussion slightly. Instead of telling our code that it smells, let’s recognize something else - our code is trying to talk to us.




Code Talks


And imagine trying to talk to someone about something important - say, the building is on fire - and them not understanding your strange gestures and telling you you are smelly. Would that make you happy? It doesn’t make our code happy. And if I can take some poetic license, I’d even say that code cries




Code Cries


And our code cries not because it is smelly, but because no one understands what it is trying to say. It’s trying to point out what it wants to do, what is important, and how to use it. And it isn’t happy about that! Too often we try to force what we want, what we think is best.




Because No One Understands What It Is

Saying

Code Cries


And our code cries not because it is smelly, but because no one understands what it is trying to say. It’s trying to point out what it wants to do, what is important, and how to use it. And it isn’t happy about that! Too often we try to force what we want, what we think is best.





“...we have so far beset ourselves with rules, and concepts, and ideas...that we have become afraid of

what will happen naturally, and convinced that we must work within a “system” and with “methods” [or] our

surroundings will come tumbling down in chaos.”

Christopher Alexander - “The Timeless Way of Building”


We turn to our UML and architecture diagrams and design documents, trying to brute force a system that will work, afraid that if we don’t - chaos. But nature *dictates* an iterative design - one where the best path is not only discovered, but continually chosen. We literally can not build software any other way.




This is a map of the Mississippi River in the United States. What’s special about it is that it is all of the routes the river has run through the years. We create a design. We settle down, build a house, have a family. But the code doesn't want that. It has plans beyond our design. And if we don't listen to those plans, our days will become filled with holding off the impending - and inevitable - change (http://www.adammandelman.net/tag/harold-fisk/)




For example, in 2011, the Mississippi River tried to change course, I believe to the Orange area. And it normally would have - except for the millions of dollars the Army Corp of Engineers spent to erect dams, flood farm fields and otherwise keep it on the course best for us - not for it. But trying to brute force design into nature’s iterative process isn’t the only problem. (10k next)




Ten Thousand Hours


There’s a common figure that is given to developers about what it takes to become great in software. Does anyone know that number? <Click> This is the number of hours to “master” a skill. But as much as we tout this, we don’t really act like this is important. People new to software either get this




Ten Thousand Hours

Ten Thousand Hours


There’s a common figure that is given to developers about what it takes to become great in software. Does anyone know that number? <Click> This is the number of hours to “master” a skill. But as much as we tout this, we don’t really act like this is important. People new to software either get this




bloody


So, confusion and frustration, or this




Empty promises! (Beaker story). Can you imagine learning C++ in 24 hours? Well, you might be able to learn syntax, but building great software isn’t just about learning syntax. Or diagrams. At the start of the talk, I quoted Alexander talking about a Timeless Way of Building - and that this way - this timeless way - is the only way buildings - or software - that are alive can be built. And if we go right to the kernel of that way, he says




“To make a building {alive}...the builder must let go of all his

willful images, and start with a void...At this stage the building’s life will come directly from your

language”Christopher Alexander - “The Timeless Way of Building”


So for us to be able to build great software, we have to be willing to let go of the diagrams. Of the syntax. Of the “Point A, Point B, flow”. And let go of the fear




“You are able to do this only when you no longer fear that

nothing will happen”

Christopher Alexander - “The Timeless Way of Building”


of the fear that if we let go, nothing will happen. Or chaos will happen. So, how do we get to the point where we feel comfortable enough to let go. And, more importantly, how do we teach others to get to that point? I think that the way that we do that is by recognizing that the heart of programming isn’t code, but communication. That’s why we call them programming languages. And we can learn a lot from how people learn languages to help us along our ten thousand hour path to get to the point where we can build alive systems by letting go




Functional Programming

Imperative Programming

Logic Programming

Static Typing

Dynamic Typing


This first is the understanding of how languages/paradigms affect our viewpoints. Roman Jakobson points out “Languages differ...must convey vs what they may convey”. “dinner with a neighbor last night”, doesn’t reveal if it was a male or female. But if I said in German, I would be obliged to (Nachbar vs Nachbarin). Functional: context of reduction of terms. Imperative: statement of the process, and logic: statement of the result. Static: abstractions sooner, dynamic: abstraction to be held off




Coding Standards Define Dialects


The second is that even within languages we have dialects. We have to agree on what that common dialect is going to be. This is traditionally the essence of coding standards - what is our agreed upon dialect?




BICS

CALP


The third is that the way we approach and learn languages is somewhat haphazard. You only need to look at any programming language book to see they all do them differently. But the process of learning a natural language is well known, and standardized regardless of the language. We can apply a similar framework to develop the skills we need to listen and understand our code




BICS

CALP

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BICS

CALP

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- Copying from the board- Reading a Map- Face to Face Conversation- Selecting food in the lunchroom






BICS

CALP

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- Following a class schedule- Telephone Conversation- Oral Presentations- Getting an absence excuse






BICS

CALP

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- Demonstrations- Basic Math Computations- Science Experiments






BICS

CALP

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- Demonstrations- Basic Math Computations- Science Experiments

- Standardized Tests- Math Concepts and Applications- Listening to a Lecture






BICS

CALP

ContextReduced

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Cognitively Demanding20Thursday, November 14, 13

This framework, which I’m calling the “Foy-Z” model (with great irreverence), looks like this. We need to start by providing context. Katas provide a container to operate with in. Koans provide language specific nuances. Principles help us analyze our code in a higher context way, while patterns forces us to think about our overall goals. So let’s look at these a little more.




BICS

CALP

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ContextEmbedded



Foy-Z






BICS

CALP

ContextReduced

ContextEmbedded



Katas

Foy-Z






BICS

CALP

ContextReduced

ContextEmbedded



Katas Koans

Foy-Z






BICS

CALP

ContextReduced

ContextEmbedded



Katas Koans

Principles

Foy-Z






BICS

CALP

ContextReduced

ContextEmbedded



Katas Koans

Principles Patterns

Foy-Z






Katas


Let’s start with Katas. First described in the software world by Pragmatic Dave Thomas, they offer the ability to practice without the solution being the cognitive challenge. In short, they allow developers to practice varying externally motivated viewpoints.




Conway’s Game of Life

- Infinite Grid of Cells- Each Cell has two states - alive or dead- Interacts with neighbors in a well known way

http://en.wikipedia.org/wiki/Conway%27s_Game_of_Life








Conway’s Game of Life - If Statement





Conway’s Game of Life - No Conditional





BICS

CALP

ContextReduced

ContextEmbedded



Katas

Foy-Z


So Katas allow us to not focus on solving the problem, but instead using the problem to explore the space of viewpoints. The context is very high - we cognitively understand the problem, so we can focus on practice. But at some point we need more - and that’s where




BICS

CALP

ContextReduced

ContextEmbedded



Katas Koans

Foy-Z


So Katas allow us to not focus on solving the problem, but instead using the problem to explore the space of viewpoints. The context is very high - we cognitively understand the problem, so we can focus on practice. But at some point we need more - and that’s where




Koans


Koans come in. Koans provide language-specific nuances - the grammar if you will. They tend to be language specific, but lower context. It’s like practicing nouns and verbs - great to do, but much better if you have some context to put them in. For example (next Edgecase Koans)




https://github.com/neo/ruby_koans


one of the more famous software Koans was by Edgecase (now called Neo). You can see in the structure it was very specific to the Ruby language - arrays, assets, blocks, etc.




Ruby Koans Asserts





Ruby Koans Arrays





BICS

CALP

ContextReduced

ContextEmbedded



Katas Koans

Foy-Z


So far, we’ve stayed in the BICS realm. BUT! We’ve learned something interesting. The Koans taught us Ruby array management, and we needed that for our exercise, so let’s revisit the Katas




Conway’s Game of Life - With Map





BICS

CALP

ContextReduced

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Katas Koans

Foy-Z


At this point, we have enough basic skills that we can begin to get into cognitively demanding work. We have the context, and the grammar, but we don’t know the optimal ways to apply the grammar. That’s where coding principles come in to play




BICS

CALP

ContextReduced

ContextEmbedded



Katas Koans

Principles

Foy-Z


At this point, we have enough basic skills that we can begin to get into cognitively demanding work. We have the context, and the grammar, but we don’t know the optimal ways to apply the grammar. That’s where coding principles come in to play




Principles


Our principles guide us in how we apply our code within the context of what we’re writing.




SOLID Principles

Do we have duplication

(implementation or conceptual)?

Single responsibilities?

LoD violations?

LSP violations?


Transition to patterns




4 Rules of Simple Design

Does this code express all of the ideas we want to express?


Patterns. 4 Rules of Simple Design. Fowler. SOLID




4 Rules of Simple Design

Does this code express all of the ideas we want to express?

Are there concepts from our domain that can be expressed?






Fowler’s Perspectives (from UML Distilled)

Are we operating at the right level -

Conceptual, Specification or Implementation?






BICS

CALP

ContextReduced

ContextEmbedded



Katas Koans

Principles

Foy-Z


At this point, we have enough basic skills that we can begin to get into cognitively demanding work. As I mentioned earlier, Design Patterns




BICS

CALP

ContextReduced

ContextEmbedded



Katas Koans

Principles Patterns

Foy-Z


At this point, we have enough basic skills that we can begin to get into cognitively demanding work. As I mentioned earlier, Design Patterns




Patterns


Design Patterns provide a guide for the forces encountered. What does that mean? We have a tendency to think of Design Patterns as recipes to make our code look a certain way. But




Patterns are something else.




Naming something the name of a pattern does not make it that pattern






Naming something the name of a pattern does not make it that pattern

Putting patterns in our code does not make our code good






Porch Swing





Swimming Pool





Hedge Trimmer


Not a pattern, but a death trap (next GoF Book / Structure of Patterns)




• Pattern Name• Intent• Also Known As• Motivation / Forces• Applicability• Structure• Participants• Collaboration• Consequences• Implementation• Sample Code• Known Uses• Related Patterns


The GoF Book wasn’t a beginners guide. It was Erich’s PhD Thesis. Patterns are designed to put into form the forces you may run into while building code. What does that mean?




Server


Let’s imagine a mobile application to upload pictures. So what forces are at play here? We know we have to associate multiple pictures to data. Data can have new types added, which need to be available on all other phones. The phone needs to be able to send the pictures to the server, as well as send and receive data updates. And deal with offline conditions.




- Countries- Products- Locations

Server







Server

- Send Data- Receive Data







MultiplePictures

Server








MultiplePictures

SendPictures

Server








MultiplePictures

SendPictures

Server


Storage Options44Thursday, November 14, 13






Offline


One way is by knowing the forces at play and comparing them to previous events. For example, the phone (or server) could be offline. What can we do if we are offline?




Offline

Not allow send Queue items to send






Offline


Automatically Manually






Offline



Forces: - User has to remember to send - User can’t do other tasks until sent - User has to send each one






Offline



Forces: - Store multiple requests - Schedule to run them - Handle failed requests - Allow user to see status

Forces: - User has to remember to send - User can’t do other tasks until sent - User has to send each one






http://www.soapatterns.org/asynchronous_queuing.php


So the patterns we choose are a result of the forces we are trying to resolve - the forces inherent in the solution itself.






BICS

CALP

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Foy-Z


So now that we’ve got a framework on how to get the point of understanding, now what? Well, our code is getting happier, because




we’ve begun addressing some of the key issues in being able to listen to it.




We don’t understand the

language







language

We don’t have common context







language


We don’t know the grammar







language



We don’t know how to apply the

grammar







language



We don’t know how to apply the

grammar

We don’t know what’s

appropriate






http://www.flickr.com/photos/jakeandlindsay/5524669257


So how to we apply it? How do we use that to now let go? First, diagrams aren’t bad. There’s nothing wrong with sketching out a plan. But, “No plan survives first contact with the enemy”. So pay attention to the forces more than the plan.








For example, looking at this pattern again, notice the impacts. We may say to ourselves, we want an Aysnc Queue, so fine, be on the lookout for that. But don’t blindly just shove an async queue in. Watch for your code to tell you it needs it. (This also applies to databases and many other things we “Know we need”)






http://marchoeijmans.blogspot.com/2013/03/test-driven-development-tdd.html(Although I disagree with the article)


Second: If you haven’t done TDD, or aren’t doing it, I’d highly recommend spending some time with Katas trying it out. What I find powerful is that it makes no qualms about your design. Don’t write a design, and then write tests to prove you are writing your design. Let the tests guide you. See what design emerges from them.



http://marchoeijmans.blogspot.com/2013/03/test-driven-development-tdd.html





Third: Technical Vision. In a team environment, you want to make sure you all are on the same page. Traditionally we’ve built software bottom up. But this doesn’t give us an opportunity to learn. “Tracer Bullets”




Database






Database

Stored Procedures






Database

Stored Procedures

Service Layer






Database

Stored Procedures

Service Layer

API Layer






Database

Stored Procedures

Service Layer

API Layer

Front End Layer






Database

Stored Procedures

Service Layer

API Layer

Front End Layer


There’s nothing wrong with a vision. And as you work on slices, you can check against the overall vision to see if you are on the path you expected, or if your vision needs to change. Not the code, but the vision.




Database

Stored Procedures

Service Layer

API Layer

Front End Layer

Vision


There’s nothing wrong with a vision. And as you work on slices, you can check against the overall vision to see if you are on the path you expected, or if your vision needs to change. Not the code, but the vision.




Pay attention to the forcesLet the code (and tests!) guide your design

Develop a vision, but use it as a guide, not a whipping post


These things together, along with the solid understanding of the different paradigms and approaches are going to get you to the point where you can let go of the “willful images” and start really listening to your code. And when you listen to your code




you end up with happy code. And when you don’t, you end up with unhappy code, baffled at why you are even bothering to build it if you aren’t going to listen.




if coder_listens?






if coder_listens? puts “:-)”






if coder_listens? puts “:-)”else






if coder_listens? puts “:-)”else puts “:`-(“






if coder_listens? puts “:-)”else puts “:`-(“end






Cory Foy (@cory_foy)

[email protected]










sqe boston - when code cries

Technology

quality code

writing code

bad code

code cries cory foy

lower right

foymodifying software

software industry

majority of software