Dart – Comments

In every programming language comments play an important role for a better understanding of the code in the future or by any other programmer. Comments are a set of statements that are not meant to be executed by the compiler. They provide proper documentation of the code. 

Types of Dart Comments: 

1. Dart Single line Comment.
2. Dart Multiline Comment.
3. Dart Documentation Comment.

1. Dart Single line Comment: Dart single line comment is used to comment a line until line break occurs. It is done using a double forward-slash (//). 

// This is a single line comment. 

Example: 

Dart

int main()
{
  double area = 3.14 * 4 * 4;
  // It prints the area
  // of a circle of radius = 4
  print(area);

return 0;
}

Output:

50.24

2. Dart Multi-Line Comment: Dart Multiline comment is used to comment out a whole section of code. It uses ‘/*’ and ‘*/’ to start and end a multi-line comment respectively. 

/* 

These are 

multiple line 

of comments 

*/ 

Example: 

Dart

int main()
{
  var lst = [1, 2, 3];

  /*
  It prints
  the whole list
  at once
  */
  print(lst);

return 0; }

Output: 

[1, 2, 3]

3. Dart Documentation Comment: Dart Documentation Comments are a special type of comment used to provide references to packages, software, or projects.Dart supports two types of documentation comments “///”(C# Style) and “/**…..*/”(JavaDoc Style). It is preferred to use “///” for doc comments as many times * is used to mark list items in a bulleted list which makes it difficult to read the comments. Doc comments are recommended for writing public APIs. 

/// This is 

/// a documentation 

/// comment 

Example: 

Dart

bool checkEven(n){
  /// Returns true
  /// if n is even
  if(n%2==0)

      return true;
  /// Returns false if n is odd
  else

      return false; }

int main()
{
  int n = 43;
  print(checkEven(n));
  return 0;
}

Output: 

false