smell your code! @ iet-kfupm patw

Smell your Code!

Yaser Sulaiman

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Our road map

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Who? What? Why? How?

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If you can take away only 1 lesson…

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Don’t Repeat Yourself!

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This rule is so important…

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I must break it!

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Don’t Repeat Yourself!

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Who? What? Why? How?

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“Who are you?”

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A scientist, not an engineer

(I probably should be doing this @ ACM, not IET)

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21 logo stolen from Kyle Usbeck

22 logo by Yukihiro Matsumoto

“You talkin’ to me?”

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Are you a software developer?

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If not, do you write code?

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If not, would you be remotely interested in writing cleaner code

and making your life easier?

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If not, you’re free to zone out

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“Why should I listen to you?”

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I won’t give you the “I’m a passionate software developer” BS

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I’ve a terminal illness

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Make that 2 terminal illnesses

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Perfectionism &

OCD

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33 photo by X.u.k.i

Who? What? Why? How?

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“Code smells?! Can I smell my code?!”

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36 photo by lanceball

Yes you can, but not with your nose

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Code smells are warning signs

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39 photo by pj_in_oz

They’re surface indications of deeper problems

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41 photo by BenChenowethWork

They’re surface indications of deeper problems

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A code smell ⇏ a problem

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Who? What? Why? How?

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The bigger picture

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Software Quality

Code Quality

Code Smells

46 not to scale

Writing HQ code should be the priority

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HQ code = easy toread

understandchange

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In the short term, HQ code may cost more

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50 photo by theresaanna

Easier to change ≈ less costly

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In the long run, HQ code costs less

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One path to cleaner code goes through code smells

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Who? What? Why? How?

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There’re many code smells

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The following smells are just a small subset

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They’re the ones that drives me crazy the most

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Code Smell #1

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The nastiest code smell

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DupIicated code DupIicated code DupIicated code DupIicated code DupIicated code DupIicated code DupIicated code DupIicated code DupIicated code DupIicated code DupIicated code DupIicated code DupIicated code DupIicated code DupIicated code DupIicated code DupIicated code DupIicated code DupIicated code DupIicated code

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Code Smell #2

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functions.With(just, way, too, many, parameters, and,

then, even, some, more)

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How many is too many?

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Steve McConnell: > 7 ± 2

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Robert C. “Uncle Bob” Martin: > 3

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Code Smell #3

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Not following a coding convention/standard/style

consistently

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69 stolen from EmacsWiki

Not following a coding convention/standard/style

consistently

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The specifics doesn’t really matter; what matters most is consistency

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Code Smell #4

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// code.CommentOut();

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Don’t get me wrong

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When you’re experimenting, comment code to your heart's

content

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Just remember to clean up after yourself

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And don’t commit commented-out

code

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“Commented-out code is an abomination.”—Uncle Bob

78 photo used with permission of Uncle Bob

Commented-out code makes Uncle Bob angry

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It makes me angry

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81 photo by tomazstolfa

Code Smell #5

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// This is a comment

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redundant

Who? What? Why? How?

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Comments should focus on

Who? What? Why? How?

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I may have come off as an a$$

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My code smells as bad as everyone else’s.. sometimes even worse

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But I’m aware of my smells

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I try my best to prevent them

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I don’t ignore them; I deal with them

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I smell my code

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You should smell your code too

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When you code, take note of your nose It should be open, not close

For an open nose leads to an open mind And that’s the best rhyme I was able to find

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If you want to sniff more…

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95 more than just code smells

…</presentation> <questions>…

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