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Declare and use variables

In this guide, we will learn how to declare and use variables in vein.

Variable Declaration

Variables in vein can be declared using the auto keyword, which deduces the type of the variable from the value it is initialized with.
Here are some examples:

Example 1: Integer Variable

vein
auto a = 1;

In this example, a is an integer variable initialized to 1.

Example 2: String Variable

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auto greeting = "Hello, World!";

Here, greeting is a string variable initialized to "Hello, World!".

Example 3: Double Variable

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auto pi = 3.14159d;

In this example, pi is a double variable initialized to 3.14159d.

Example 4: Boolean Variable

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auto isActive = true;

Here, isActive is a boolean variable initialized to true.

Usage of Variables

Once you declare a variable, you can use it in your code.
Here's an example of using variables:

Example: Using Variables in a Class

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#use "std"

class Prog {
   master(): void {
      auto message = "Hello, World!";
      auto number = 42;
      auto isActive = true;

      Out.println(message);
      Out.println("Number: " + number);
      Out.println("Active: " + isActive);
   }
}

In this example:

  • message is a string variable.
  • number is an integer variable.
  • isActive is a boolean variable.

The Out.println method is used to print the values of these variables.

Best Practices

  • Use meaningful variable names: Choose names that clearly indicate the purpose of the variable.
  • Keep scope in mind: Declare variables in the smallest scope possible to improve readability and maintainability.
  • Consistency: Stick to a consistent naming convention throughout your codebase.

Conclusion

Now that you know how to declare and use variables, you can begin incorporating them into your programs.
Experiment with different data types and operations to get a feel for how variables work in vein.