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Clean code exercises - part 1

Eder Díaz on November 19, 2020

Illustration by Ivan Haidutski from Icons8 You've probably read and listen a lot about Clean Code and probably you're tired of acronyms like YAGNI...
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jonrandy profile image
Jon Randy 🎖️ •

If, in a code interview, someone wrote code along the lines of:

function someFunction() {
  if (someBooleanExpression) {
    return true
  }
  return false
}
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I wouldn't hire them

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alexmario74 profile image
Mario Santini •

I would like to know why?

I think that clean code is not the main concern on a whiteboard job interview.
But cleaning up some code can also be a good question for a candidate.

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jonrandy profile image
Jon Randy 🎖️ • • Edited

The if and two returns are entirely superfluous. This type of code to me indicates a lack of understanding of what a boolean expression is. My above example should really be written:

function someFunction() {
  return someBooleanExpression
}
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Or, better still:

const someFunction = () => someBooleanExpression
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There is nothing tricky or clever going on in my code. Being overly verbose is not the same as being clean

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alexmario74 profile image
Mario Santini •

I see.

I think that writing pseudo code on a whiteboard explaining what I have in mind, it's not the same as writing production code.

The uncecessary if and return statement will help exposing the implementation to another humans.

It's just that, I often refctor boolean expressions as you did here, so it is just that I was courious about your reasons about failing a job interview.

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jonrandy profile image
Jon Randy 🎖️ •

The code should never be written that way in the first place - it's as bad as writing something like this in pseudocode:

if true return true else return false
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Definitely a red flag

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ogzhanolguncu profile image
Oğuzhan Olguncu •

Also, violates SOLID's first principle, because now function
does two thing instead one.

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darkwiiplayer profile image
𒎏Wii 🏳️‍⚧️ • 
const circleStrategy = (shape) => Math.PI * shape.radius * shape.radius

const squareStrategy = (shape) => shape.width * shape.width

const rectangleStrategy = (shape) => shape.width * shape.height
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Those functions are poorly named. Proper names would be areaCircle, areaSquare and areaRectangle respectively. You can turn the names around, but putting area first makes for easier sorting.

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ederchrono profile image
Eder Díaz •

Yeah I wasn't too careful with the naming here since that wasn't the problem of the exercise. I think that calculateAreaCircle would be better though, since methods should have a present tense verb.

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darkwiiplayer profile image
𒎏Wii 🏳️‍⚧️ •

since methods should have a present tense verb

I don't see any methods in that code.

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schmelto profile image
Tom Schmelzer •

Nice and easy understanding. Thanks for sharing :)