Unlocking the Power of Variables in Rust
Storing Data with Ease
In the world of computer programming, variables play a vital role in storing data. Think of them as labeled containers that hold information, making it easy to access and manipulate. In Rust, we use the let
keyword to declare a variable, followed by the variable name and its assigned value.
Meet the Variables
Let’s create three different variables: age
to store an integer value, salary
to store a floating-point data, and name
to store a string. We’ll use the println!
macro to print these variables, showcasing their values.
The Mutability Conundrum
By default, Rust variables are immutable, meaning their values cannot be changed once defined. But what if we need to update a variable? Rust allows us to create mutable variables using the mut
keyword before the variable name. This way, we can change the value of a variable whenever needed.
Breaking the Immutable Barrier
Let’s see an example of how we can create a mutable variable x
and change its value from 1 to 2. With the mut
keyword, we can update the value of x
without any errors.
The Art of Naming Variables
When it comes to naming variables in Rust, there are some essential rules to follow:
- Rust is case-sensitive, so
age
andAGE
are treated as different variables. - Variable names must start with a letter or an underscore.
- Only letters, digits, and underscores are allowed in variable names.
- Use underscores to separate words in variable names.
The Power of Constants
Constants are special variables whose values cannot be changed. We use the const
keyword to create constants in Rust. Let’s declare a constant PI
with a value of 3.14. Now, the value of PI
remains unchanged throughout the program.
The Error of Changing Constants
What happens if we try to change the value of a constant? Rust will throw an error, ensuring the integrity of our program. Note that Rust’s naming convention dictates using uppercase letters for constant names.