Mudanças entre as edições de "Use Intent Revealing Names"

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1. What kinds of things are in theList?
 
1. What kinds of things are in theList?
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2. What is the significance of the zeroth subscript of an item in theList?
 
2. What is the significance of the zeroth subscript of an item in theList?
3. What is the significance of the value 4?
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3. What is the significance of the value?
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4. How would I use the list being returned?
 
4. How would I use the list being returned?
  

Edição das 10h36min de 27 de janeiro de 2020

It is easy to say that names should reveal intent. What we want to impress upon you is that we are serious about this. Choosing good names takes time but saves more than it takes.

So take care with your names and change them when you find better ones. Everyone who reads your code (including you) will be happier if you do.

The name of a variable, function, or class, should answer all the big questions. It should tell you why it exists, what it does, and how it is used. If a name requires a comment, then the name does not reveal its intent.

int d; // elapsed time in days

The name d reveals nothing. It does not evoke a sense of elapsed time, nor of days. We should choose a name that specifies what is being measured and the unit of that measurement:

int elapsedTimeInDays;
int daysSinceCreation;
int daysSinceModification;
int fileAgeInDays;

Choosing names that reveal intent can make it much easier to understand and change code. What is the purpose of this code?

 public List<int[]> getThem() {
     List<int[]> list1 = new ArrayList<int[]>();
     for (int[] x : theList)
         if (x[0] == 4)
             list1.add(x);
     return list1;
 }

Why is it hard to tell what this code is doing? There are no complex expressions. Spacing and indentation are reasonable. There are only three variables and two constants mentioned. There aren’t even any fancy classes or polymorphic methods, just a list of arrays (or so it seems).

The problem isn’t the simplicity of the code but the implicity of the code (to coin a phrase): the degree to which the context is not explicit in the code itself. The code implicitly requires that we know the answers to questions such as:

1. What kinds of things are in theList?

2. What is the significance of the zeroth subscript of an item in theList?

3. What is the significance of the value?

4. How would I use the list being returned?

Avoid Disinformation