After the success of our last article on mastering type guards, I decided to create an NPM library to help streamline the process. Introducing type-guards-ts, a comprehensive library designed to enhance your TypeScript projects with advanced type guard techniques!

Ready to master TypeScript type guards? Dive into this article to learn how to use type-guards-ts and make your code more robust and type-safe.

🔗 Package: https://www.npmjs.com/package/type-guards-ts

Mastering Type Guards with type-guards-ts

Description

type-guards-ts is a powerful TypeScript library that provides a collection of type guard functions to help you perform runtime type checks and type narrowing. This library includes functions to check if a value is of a certain type (e.g., isBoolean) and functions to check if a value is not of a certain type (e.g., isNotBoolean).

Installation

To install the package, run the following command:

npm install type-guards-ts

How to Use

To use the type guards provided by type-guards-ts, import the required functions from the package and use them in your TypeScript code.

import { isBoolean } from "type-guards-ts";

const value: unknown = true;

if (isBoolean(value)) {
    // TypeScript now knows that `value` is a boolean
    console.log("The value is a boolean.");
} else {
    console.log("The value is not a boolean.");
}

Available Type Guards

is-type

• isBigInt
• isBoolean
• isFunction
• isNull
• isNumber
• isObject
• isString
• isSymbol
• isUndefined

is-not-type

• isNotBigInt
• isNotBoolean
• isNotFunction
• isNotNull
• isNotNumber
• isNotObject
• isNotString
• isNotSymbol
• isNotUndefined

How to Use Key Type Guards

isNull

Checks if a value is null.

import { isNull } from "type-guards-ts";

const value: unknown = null;

if (isNull(value)) {
    console.log("The value is null.");
} else {
    console.log("The value is not null.");
}

isNotNull

Checks if a value is not null.

import { isNotNull } from "type-guards-ts";

const value: unknown = "Some value";

if (isNotNull(value)) {
    console.log("The value is not null.");
} else {
    console.log("The value is null.");
}

isString

Checks if a value is a string.

import { isString } from "type-guards-ts";

const value: unknown = "Hello, world!";

if (isString(value)) {
    console.log("The value is a string.");
} else {
    console.log("The value is not a string.");
}

isNotString

Checks if a value is not a string.

import { isNotString } from "type-guards-ts";

const value: unknown = 42;

if (isNotString(value)) {
    console.log("The value is not a string.");
} else {
    console.log("The value is a string.");
}

isNumber

Checks if a value is a number.

import { isNumber } from "type-guards-ts";

const value: unknown = 42;

if (isNumber(value)) {
    console.log("The value is a number.");
} else {
    console.log("The value is not a number.");
}

isNotNumber

Checks if a value is not a number.

import { isNotNumber } from "type-guards-ts";

const value: unknown = "42";

if (isNotNumber(value)) {
    console.log("The value is not a number.");
} else {
    console.log("The value is a number.");
}

Conclusion

Type guards in TypeScript provide a powerful way to ensure type safety and improve code reliability. By using type-guards-ts, you can handle complex type checks efficiently and avoid common pitfalls associated with dynamic types. Leveraging these techniques will help you write cleaner, more maintainable code, ultimately leading to more robust applications.

🚀 Ready to elevate your TypeScript skills? Install type-guards-ts today and ensure safe type checks in your projects!

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