3.4. Dart Basics: Looping Structures

Dart is a modern programming language, developed by Google, that allows the creation of high-performance applications for several platforms using a single code base. It is the language used in the Flutter framework, which is gaining more and more popularity in the development of mobile applications. In this text, we are going to approach one of the basic concepts of Dart: the repetition structures.

The repetition structures, also known as loops, are fundamental in any programming language. They allow a block of code to be repeated multiple times, which can be extremely useful in many situations. In Dart, we have three main looping structures: for, while, and do-while.

The for loop is probably the most commonly used loop structure. It is composed of three parts: initialization, condition and increment. Let's see an example:

for (int i = 0; i < 10; i++) {
  print(i);
}

In the example above, the variable i is initialized with the value 0. Then, as long as i is less than 10, the block of code inside the braces will be executed and the value of i will be incremented by 1 with each repetition. Thus, the numbers from 0 to 9 will be printed on the screen.

The while loop is another loop structure in Dart. It is a little simpler than for, as it only consists of one condition. The block of code inside the while will be repeated as long as the condition is true. Let's see an example:

int i = 0;
while (i < 10) {
  print(i);
  i++;
}

This example will do exactly the same thing as the previous example with the for. The difference is that initialization and incrementing of the variable i is done outside the loop.

Finally, we have the do-while loop. It is very similar to while, but with one fundamental difference: the block of code inside the do-while will be executed at least once, regardless of the condition. This is because the condition is only checked after the first run. Let's see an example:

int i = 0;
of {
  print(i);
  i++;
} while (i < 10);

Again, this example will do the same thing as the previous two examples. The difference is that even if i were initialized to a value greater than or equal to 10, the code block inside the do-while would be executed at least once.

The repetition structures are essential tools for any programmer and are widely used in several situations, such as list processing, flow control, among others. Mastering these concepts is critical to creating efficient and performant apps with Dart and Flutter.

With an understanding of these looping structures, you will be better equipped to deal with the programming logic required to develop applications. Keep studying and practicing to become even more familiar with these concepts and become a competent Dart and Flutter developer.

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23Dart Basics: Functions

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