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Programming

17 Subtle Rules of Software Engineering

List By: Miko Pawlikowski  Descriptions By: Jessica Brown Published: December 29, 2024 Software engineering is a discipline that balances technical precision, creativity, and collaboration. These 17 subtle rules provide insights to improve the quality of code, foster teamwork, and guide sustainable practices. 0. Stop Falling in Love with Your Own Code When you become too attached to your code, you may resist valuable feedback or overlook its flaws. Always prioritize the quality of the solution
Book Recommendations

📚 Recommended Linux Books to Read for Jan. 31, 2025

Linux in a Nutshell Author(s): Jessica Perry Hekman, Ellen Siever, Aaron Weber, Stephen Figgins, Robert Love, Arnold Robbins, Stephen Spainhour Linux in a Nutshell: An In-Depth Review "Linux in a Nutshell", is a prodigious technical reference book penned by an impressive team of authors – Jessica Perry Hekman, Ellen Siever, Aaron Weber, Stephen Figgins, Arnold Robbins, Stephen Spainhour and Robert Love. It provides a comprehensive and utterly engaging tour of the Linux operating system for begin
Book Recommendations

Why Every SysAdmin Should Understand ISO/IEC 27001:2022

In today’s digital landscape, the role of a System Administrator (SysAdmin) extends far beyond server uptime and software updates. With cyber threats evolving daily, understanding key information security standards like ISO/IEC 27001:2022 is no longer optional, it’s essential. This international standard provides a robust framework for establishing, implementing, maintaining, and continuously improving an Information Security Management System (ISMS). For SysAdmins, mastering ISO/IEC 27001 isn’t
Book Recommendations

📚 Recommended Servers Books to Read for Jan. 31, 2025

Web Server Programming Author(s): Neil Gray Subject: servers 'Web Server Programming' Explored: An Enlightening Dive into Digital Engineering As someone deeply entrenched in the world of literature, there are books that unravel their mysteries instantly and others that unfold their knowledge meticulously. Falling gleefully into the latter category is Web Server Programming by Neil Gray. In this technologically intensive era, Gray masterfully deciphers the art of web server programming, venturing
Book Recommendations

📚 Recommended Programming Books to Read for Jan. 31, 2025

Reconfigurable Processor Array a Bit Sliced Parallel Computer (USA) Author(s): A. Rushton Subject: programming The Breakthrough of Parallel Computing: A Review of A. Rushton's 'Reconfigurable Processor Array a Bit Sliced Parallel Computer (USA)' In the ever-evolving world of technology, keeping up with the innovation and concepts that define the landscape can be a challenge. Yet, in his book, 'Reconfigurable Processor Array - A Bit Sliced Parallel Computer (USA)', A. Rushton provides a solid f
Computing

ArmSoM AIM7: A Promising Upcoming Rockchip Device for AI Development

by: Abhishek Kumar When ArmSoM kindly offered to send me their upcoming RK3588 AI Module 7 (AIM7), along with the AIM-IO carrier board, I was thrilled. Having worked with AI hardware like Nvidia’s Jetson Nano and Raspberry Pi boards, I’m always curious about devices that promise powerful AI capabilities without requiring a large physical setup or heavy power draw. The RK3588 AI Module 7 (AIM7), powered by the Rockchip RK3588, seemed to hit that sweet spot, a compact module with robust process

How to Prepare for Data Scientist Interview in 2025?

by: Neeraj Mishra Sat, 11 Jan 2025 10:39:00 +0000 One of the fastest-growing domains in the recent years is data science. For those who don’t know, data science revolves around different subjects that ultimately lead to one goal. Subjects include math, statistics, specialized programming, advanced analytics, machine learning, and AI. Working with these subjects, a data scientist uses his expertise to help generate useful insights for guiding an organization with respect to the data they have. O
Tutorials

Regular Expression Tutorial (TOC)

Regular Expressions Tutorial Table of Contents Regular Expression Tutorial pg 1 Word Boundaries pg 10 Understanding Atomic Grouping in Regular Expressions pg 19 Different Regular Expression Engines pg 2 Alternation with the Vertical Bar or Pipeline Symbol pg 11 Understanding Lookahead and Lookbehind in Regular Expressions (Lookaround) pg 20 Literal Characters pg 3 Optional Items pg 12 Testing Multiple Conditions on the Same Part of a String with Lookaround pg 21 Special Characters pg 4 Repetitio
Tutorials

Free-Spacing Mode in Regular Expressions: Improving Readability (Page 27)

Free-spacing mode, also known as whitespace-insensitive mode, allows you to write regular expressions with added spaces, tabs, and line breaks to make them more readable. This mode is supported by many popular regex engines, including JGsoft, .NET, Java, Perl, PCRE, Python, Ruby, and XPath. How to Enable Free-Spacing Mode To activate free-spacing mode, you can use the mode modifier (?x) within your regex. Alternatively, many programming languages and applications offer options to enable free-spa
Tutorials

Adding Comments to Regular Expressions: Making Your Regex More Readable (Page 26)

Regular expressions can quickly become complex and difficult to understand, especially when dealing with long patterns. To make them easier to read and maintain, many modern regex engines allow you to add comments directly into your regex patterns. This makes it possible to explain what each part of the expression does, reducing confusion and improving readability. How to Add Comments in Regular Expressions The syntax for adding a comment inside a regex is: (?#comment) The text inside the parent
Tutorials

Understanding POSIX Bracket Expressions in Regular Expressions (Page 25)

POSIX bracket expressions are a specialized type of character class used in regular expressions. Like standard character classes, they match a single character from a specified set of characters. However, they offer additional features such as locale support and unique character classes that aren't found in other regex flavors. Key Differences Between POSIX Bracket Expressions and Standard Character Classes POSIX bracket expressions are enclosed in square brackets ([]), just like regular charact
Tutorials

XML Schema Character Classes and Subtraction Explained (Page 24)

XML Schema introduces unique character classes and features not commonly found in other regular expression flavors. These classes are particularly useful for validating XML names and values, making XML Schema regex syntax essential for working with XML data. Special Character Classes in XML Schema In addition to the six standard shorthand character classes (e.g., \d for digits, \w for word characters), XML Schema introduces four unique shorthand character classes designed specifically for XML na
Tutorials

Using If-Then-Else Conditionals in Regular Expressions (Page 23)

Conditional logic isn’t limited to programming languages — many modern regular expression engines allow if-then-else conditionals. This feature lets you apply different matching patterns based on a condition. The syntax for conditionals is: (?(condition)then|else) If the condition is met, the then part is attempted. If the condition is not met, the else part is applied instead. You can omit the else part if it’s not needed. Conditional Syntax and How It Works The syntax for if-then-else conditio
Tutorials

Understanding the \G Anchor in Regular Expressions (Page 22)

The \G anchor is a powerful tool in regular expressions, allowing matches to continue from the point where the previous match ended. It behaves similarly to the start-of-string anchor \A on the first match attempt, but its real utility shines when used in consecutive matches within the same string. How the \G Anchor Works The anchor \G matches the position immediately following the last successful match. During the initial match attempt, it behaves like \A, matching the start of the string. On s
Tutorials

Testing Multiple Conditions on the Same Part of a String with Lookaround (Page 21)

In regular expressions, it’s common to need a match that satisfies multiple conditions simultaneously. This is where lookahead and lookbehind, collectively known as lookaround assertions, come in handy. These zero-width assertions allow the regex engine to test conditions without consuming characters in the string, making it possible to apply multiple requirements to the same portion of text. Why Lookaround Is Essential Let’s say you want to match a six-letter word that contains the sequence “ca
Tutorials

Understanding Lookahead and Lookbehind in Regular Expressions (Lookaround) (Page 20)

Lookahead and lookbehind, often referred to collectively as "lookaround," are powerful constructs introduced in Perl 5 and supported by most modern regular expression engines. They are also known as zero-width assertions because they don’t consume characters in the input string. Instead, they simply assert whether a certain condition is true at a given position without including the matched text in the overall match result. Lookaround constructs allow you to build more flexible and efficient reg
Tutorials

Understanding Atomic Grouping in Regular Expressions (Page 19)

Atomic grouping is a powerful tool in regular expressions that helps optimize pattern matching by preventing unnecessary backtracking. Once the regex engine exits an atomic group, it discards all backtracking points created within that group, making it more efficient. Unlike regular groups, atomic groups are non-capturing, and their syntax is represented by (?:?>group). Lookaround assertions like (?=...) and (?!...) are inherently atomic as well. Atomic grouping is supported by many popular r
Tutorials

Possessive Quantifiers (Page 18)

When working with repetition operators (also known as quantifiers) in regular expressions, it’s essential to understand the difference between greedy, lazy, and possessive quantifiers. Greedy and lazy quantifiers affect the order in which the regex engine tries to match permutations of the pattern. However, both types still allow the regex engine to backtrack through the pattern to find a match. Possessive quantifiers take a different approach—they do not allow backtracking once a match is made,
Computing

Remembering Usenet - The OG Social Network that Existed Even Before the World Wide Web

by: Bill Dyer Before Reddit, before GitHub, and even before the World Wide Web went online, there was Usenet. This decentralized network of discussion groups was a main line of communication of the early internet - ideas were exchanged, debates raged, research conducted, and friendships formed. For those of us who experienced it, Usenet was more than just a communication tool; it was a community, a center of innovation, and a proving ground for the ideas. 📋 It is also culturally and historic
Tutorials

Regex Matching Modes (Page 17)

Most regular expression engines discussed in this tutorial support the following four matching modes: Modifier Description /i Makes the regex case-insensitive. /s Enables "single-line mode," making the dot (.) match newlines. /m Enables "multi-line mode," allowing caret (^) and dollar ($) to match at the start and end of each line. /x Enables "free-spacing mode," where whitespace is ignored, and # can be used for comments. Specifying Modes Inside The Regular Expression You can specify these mode
Tutorials

Unicode Regular Expressions (Page 16)

Unicode regular expressions are essential for working with text in multiple languages and character sets. As the world becomes more interconnected, supporting Unicode is increasingly important for ensuring that software can handle diverse text inputs. What is Unicode? Unicode is a standardized character set that encompasses characters and glyphs from all human languages, both living and dead. It aims to provide a consistent way to represent characters from different languages, eliminating the ne
Tutorials

Named Capturing Groups (Page 15)

Named capturing groups allow you to assign names to capturing groups, making it easier to reference them in complex regular expressions. This feature is available in most modern regular expression engines. Why Use Named Capturing Groups? In traditional regular expressions, capturing groups are referenced by their numbers (e.g., \1, \2). As the number of groups increases, it becomes harder to manage and understand which group corresponds to which part of the match. Named capturing groups solve th
Tutorials

Grouping with Round Brackets (Page 14)

In regular expressions, round brackets (()) are used for grouping. Grouping allows you to apply operators to multiple tokens at once. For example, you can make an entire group optional or repeat the entire group using repetition operators. Basic Usage For example: Set(Value)? This pattern matches: "Set" "SetValue" The round brackets group "Value", and the question mark makes it optional. Note: Square brackets ([]) define character classes. Curly braces ({}) specify repetition counts. Only ro
Tutorials

Repetition with Star and Plus (Page 13)

In addition to the question mark, regex provides two more repetition operators: the asterisk (*) and the plus (+). Basic Usage The * (star) matches the preceding token zero or more times. The + (plus) matches the preceding token one or more times. For example: <[A-Za-z][A-Za-z0-9]*> This pattern matches HTML tags without attributes: <[A-Za-z] matches the first letter. [A-Za-z0-9]* matches zero or more alphanumeric characters after the first letter. This regex will match tags like: <
Tutorials

Optional Items (Page 12)

The question mark (?) makes the preceding token in a regular expression optional. This means that the regex engine will try to match the token if it is present, but it won’t fail if the token is absent. Basic Usage For example: colou?r This pattern matches both "colour" and "color." The u is optional due to the question mark. You can make multiple tokens optional by grouping them with round brackets and placing a question mark after the closing bracket: Nov(ember)? This regex matches both "Nov"
Tutorials

Alternation with the Vertical Bar or Pipe Symbol (Page 11)

Previously, we explored how character classes allow you to match a single character out of several possible options. Alternation, on the other hand, enables you to match one of several possible regular expressions. The vertical bar or pipe symbol (|) is used for alternation. It acts as an OR operator within a regex. Basic Syntax To search for either "cat" or "dog," use the pattern: cat|dog You can add more options as needed: cat|dog|mouse|fish The regex engine will match any of these options. Fo
Tutorials

Word Boundaries (Page 10)

The \b metacharacter is an anchor, similar to the caret (^) and dollar sign ($). It matches a zero-length position called a word boundary. Word boundaries allow you to perform “whole word” searches in a string using patterns like \bword\b. What is a Word Boundary? A word boundary occurs at three possible positions in a string: Before the first character if it is a word character. After the last character if it is a word character. Between two characters where one is a word character and the ot
Tutorials

Start of String and End of String Anchors (Page 9)

In previous sections, we explored how literal characters and character classes operate in regular expressions. These match specific characters in a string. Anchors, however, are different. They match positions in the string rather than characters, allowing you to "anchor" your regex to the start or end of a string or line. Using the Caret (^) Anchor The caret (^) matches the position before the first character of the string. For example: ^a applied to "abc" matches "a." ^b does not match "abc"

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