Friday 20 September 2024

How to Check if an Array Includes a Value in JavaScript: The Modern Way


When working with JavaScript arrays, one of the most common tasks is to check whether a certain value exists within an array. Historically, this required writing loops or using methods that were not always intuitive. However, modern JavaScript provides more concise and readable solutions. Let’s explore the best methods for checking if an array contains a value and why you should use them.

1. The Modern Way: Array.prototype.includes()

Starting with ECMAScript 2016 (ES7), JavaScript introduced the includes() method, which is the easiest and most efficient way to check if an array contains a value. It is widely supported by all modern browsers, except for older versions of Internet Explorer.

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Thursday 19 September 2024

How to Quickly Create a Large File on Linux

Creating large files efficiently on Linux can be crucial, especially for testing purposes like simulating disk usage or creating virtual machine (VM) images. While tools like dd are commonly used, they can be slow. Here’s a breakdown of faster methods to create large files, avoiding slow disk writes while ensuring the file is allocated on the disk.

1. Using fallocate (Best Choice for Most Cases)

The fallocate command is the fastest way to create large files, as it allocates the required disk space without initializing or writing data. This method ensures that the entire space is reserved without wasting time.

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Wednesday 18 September 2024

Secure Hashing and Salt for PHP Passwords: A Modern Approach


When considering password protection in PHP, it’s crucial to employ up-to-date techniques to ensure both security and performance. The original question was raised in 2008, but PHP has evolved since then, providing built-in functions for safe password handling. Here’s a modern take on the subject, utilizing best practices and avoiding deprecated approaches like MD5 or SHA1.

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Tuesday 17 September 2024

Hidden Features of Perl


Perl is known for its flexibility and numerous unique features, many of which might be considered “hidden” because they are not commonly used or are esoteric. Here are some of the most intriguing hidden features of Perl that are surprisingly useful in real-world applications:

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Monday 16 September 2024

Generating Random Integers in Java: A Comprehensive Guide


In Java, generating random integers within a specific range is a common requirement for many applications, whether it’s for simulations, gaming, or data sampling. Several methods exist for this task, each with its own nuances. This post explores various approaches to generating random integers in Java, avoiding common pitfalls and highlighting the improvements made in newer Java versions.

The Pitfalls of Basic Math.random() Method

One of the simplest ways to generate random numbers in Java is by using the Math.random() function. It generates a random double value in the range [0.0, 1.0). To generate an integer within a specific range, you can scale and shift this result.

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Sunday 15 September 2024

How to Run a Local Shell Script on a Remote Machine via SSH

If you want to run a local shell script on a remote machine using SSH, there are several ways to achieve this depending on whether you’re using a Windows or Unix-based system. Here’s a guide for both environments:

For Unix-Based Systems (Linux/macOS)

You can use ssh to execute a local shell script on a remote machine without needing to copy the script over. The command works by sending the script via standard input to be executed on the remote server:

ssh user@MachineB 'bash -s' < local_script.sh
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Saturday 14 September 2024

How to Specify Multiple Return Types Using Type Hints in Python

How to Specify Multiple Return Types Using Type Hints in Python

In Python, type hints improve code readability and help developers understand what kind of values are expected for function arguments and returns. But sometimes, a function can return multiple types, which raises the question: how can we specify these multiple return types?

In this blog post, I’ll walk you through different ways to handle multiple return types using Python type hints, covering various versions of Python and how to use unions, tuples, and type-checking libraries.

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Friday 13 September 2024

Which Equals Operator (== vs ===) Should Be Used in JavaScript Comparisons?

When working with JavaScript, you have two main options for checking equality between values: the double equals (==) and the triple equals (===) operators. Both are used to compare values, but they function differently, particularly regarding type conversion.

Understanding == (Equality Operator)

The == operator, also known as the equality operator, compares two values for equality after performing type conversion. This means that if the values being compared are of different types, JavaScript will attempt to convert them to a common type before making the comparison.

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Thursday 12 September 2024

Exploring Enumerations in PHP: Workarounds and Native Support in PHP 8.1


Enumerations (enums) are a popular feature in many programming languages like Java, allowing developers to define a set of named values. However, until recently, PHP did not have native support for enums, which led developers to create various workarounds to mimic their behavior. This blog post explores different approaches to using enums in PHP, from traditional workarounds to the native support introduced in PHP 8.1.

The Challenge: Enums in PHP Before 8.1

Before PHP 8.1, developers who were used to the enum functionality from languages like Java faced challenges in PHP. Enums are beneficial because they allow for predefined, immutable sets of values that can be used for things like status codes, types, or other categories. However, PHP’s lack of native enum support led to several issues:

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Wednesday 11 September 2024

How to Get File Creation and Modification Dates/Times in Shell/Bash

 When working with files in a shell or bash environment, it’s often useful to retrieve metadata such as file creation and modification dates/times. Below are several methods to achieve this across different platforms like Linux and Windows.

1. Modification Date/Time

Retrieving the modification date and time of a file is straightforward and works across both Linux and Windows platforms.

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Tuesday 10 September 2024

Performing Perl Substitution Without Modifying the Original String

Introduction

When working with strings in Perl, a frequent task is to perform substitutions using regular expressions. However, there are times when you want to keep the original string intact while storing the modified version in a new variable. In this blog post, we’ll explore various ways to achieve this in Perl, ensuring that your original string remains unchanged while you work with its modified copy.

The Traditional Method: Copy and Modify

The most straightforward approach to perform a substitution while preserving the original string is to first copy the string to a new variable and then apply the substitution to the copy.

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Monday 9 September 2024

How to Run a Local Shell Script on a Remote Machine Using SSH

Running a local shell script on a remote machine using SSH is a common task in system administration and software development. This process allows you to execute a script on a remote server without manually copying it over. Here’s how you can do it depending on your local machine’s operating system:

For Unix-based Systems (Linux/macOS):

If your local machine is Unix-based, you can use the ssh command with input redirection to execute a local script on a remote machine. Here’s the basic syntax:

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Saturday 7 September 2024

Avoiding Null Checks in Java: Strategies for Cleaner and More Reliable Code


NullPointerExceptions (NPEs) are among the most common runtime errors in Java, and they usually arise when developers attempt to invoke methods or access fields on a null reference. To prevent NPEs, many developers rely on checking for null values before performing operations, typically using constructs like x != null. While this approach is effective, it can clutter your code and make it harder to maintain. In this blog post, we’ll explore alternative strategies to avoid null checks, leading to cleaner and more reliable Java code.

Why Avoid Null Checks?

Relying heavily on null checks can make your code verbose and harder to read. Here are some reasons why you should consider alternative approaches:

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Friday 6 September 2024

Getting the Current Date and Time in Python: A Practical Guide

Python offers a variety of ways to retrieve the current date and time, breaking it down into individual components such as year, month, day, hour, and minute. This functionality is crucial in many applications, ranging from logging events to timestamping data entries. In this post, we will explore different methods to achieve this, highlighting a few alternatives beyond the commonly used datetime module.

Method 1: Using time and struct_time

The time module provides a straightforward way to access the current time and break it down into its components. Here’s how you can use time.localtime():

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Thursday 5 September 2024

Removing Duplicates from an Array in Perl

When working with arrays in Perl, you might encounter situations where you need to remove duplicate elements. Perl, with its versatile data structures, offers several ways to accomplish this task. Let’s explore different approaches to remove duplicates from an array, demonstrating the flexibility and power of Perl.

Approach 1: Using a Hash to Filter Unique Elements

One of the simplest and most efficient ways to remove duplicates from an array is by using a hash. Hashes in Perl inherently prevent duplicate keys, which makes them ideal for this task.

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Wednesday 4 September 2024

How to Convert an InputStream into a String in Java

When working with Java, it’s common to encounter situations where you need to convert an InputStream into a String. Whether you’re reading data from a file, network socket, or other sources, understanding how to efficiently perform this conversion is crucial.

Why Convert an InputStream to a String?

An InputStream is a stream of bytes that you can read from. However, when working with text data, you often need to convert these bytes into a String. For example, you might want to:

  • Log the content of a stream.
  • Process text data from a file.
  • Pass text data between different parts of an application.
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Tuesday 3 September 2024

How to Call Shell Commands from Ruby: A Comprehensive Guide

In Ruby, interacting with the system shell is straightforward, allowing you to execute commands, capture output, and handle errors efficiently. Whether you’re automating tasks, running scripts, or managing system operations, Ruby offers multiple ways to interact with the shell. In this guide, we’ll explore various methods to call shell commands from within a Ruby program and how to handle their outputs and errors.

1. Using Backticks (`command`)

The simplest way to execute a shell command in Ruby is by using backticks. This method runs the command in a subshell and returns its standard output as a string.

output = `echo 'Hello, World!'`
puts output
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Monday 2 September 2024

Troubleshooting Python in Git Bash on Windows: A Guide with Solutions

Encountering issues when trying to run Python in Git Bash on Windows is a common problem that many developers face. If you’ve found that typing python in your Git Bash command line results in the terminal freezing without any error messages or output, you’re not alone. In this post, we will explore different ways to troubleshoot and resolve this issue, offering both temporary and permanent solutions.

The Problem

The issue arises when you try to run Python directly from Git Bash, only to find that the terminal becomes unresponsive or simply sits idle without launching the Python interpreter. This behavior is different from what you might experience in PowerShell, where Python runs without any problems. Here’s what the problem might look like in your Git Bash terminal:

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Sunday 1 September 2024

Removing a Property from a JavaScript Object


In JavaScript, removing a property from an object is a common task that can be accomplished using the delete operator. This operator allows you to remove a property from an object, making it easier to manage object data dynamically.

The delete Operator

The delete operator removes a property from an object. If the property does not exist, the operation will have no effect but will still return true. Here’s how you can use it:

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