What is Static Typing

Introduction

In this article I will be talking about what is static typing and will be showing you examples of how it is used.

Static Typing

Static typing is a secure typing system where we define data types so for example if a variable is going to contain an integer value then it will be defined with the int data type depending on what language your using. Having static typing allows you to detect errors in your code during development which you can then fix and it makes your application more secure from malicious attacks.

Type Safety Example

Here is a function in JavaScript which adds two numbers:

function add(a, b) { 
    return a + b; 
} 
console.log(add(5, 10)); // Output: 15 
console.log(add("5", "10")); // Output: "510" 
// (concatenation instead of addition)

In JavaScript the add function doesn't specify the types for its variables and because of this we can pass non integer values like strings to the function and it will concatenate the string values in the output.

In a statically typed language like Typescript, the same function will look like this:

function add(a: number, b: number):
    number { return a + b; } 
console.log(add(5, 10)); // Output: 15 
console.log(add("5", "10")); // Output Error: Argument of type '"5"' is not 
// assignable to parameter of type 'number'.

Here as you can see in TypeScript we can define our variables with the data type number to specify what type of value the function can accept, in this case integers. Now if we attempt to pass strings to the function, you will see that we get an error message Argument of type '"5"' is not assignable to parameter of type 'number' . This is happening because we have defined our variables to only accept integer values by assigning the number data type. Hopefully now you see how having type security makes your program more robust and less prone to malicious attacks.

References

https://swalih.hashnode.dev/for-those-javascript-people-who-havent-tried-typescript