Stories with Tag esoteric languages

• I learned Snobol and then wrote a toy Forth

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  Posted: 2025-05-11 06:38:27

  Verbose tl;dr

  Fascinated by Snobol's unique string-centric nature and pattern matching capabilities, the author decided to learn the language. They found its table-driven implementation particularly intriguing, inspiring them to explore implementing a similar structure for a different language. This led to the creation of a small, experimental Forth interpreter written in Snobol, showcasing how Snobol's pattern matching could effectively parse and execute Forth code. The project served as a practical exercise to solidify their understanding of Snobol while exploring the underlying mechanics of language implementation.

  The author of the blog post "I learned Snobol and then wrote a toy Forth" embarks on a personal journey of programming language exploration, beginning with Snobol4. Intrigued by its unique pattern-matching capabilities and string manipulation prowess, the author delves into the intricacies of Snobol4, highlighting its distinctive features such as its reliance on success or failure of pattern matching for control flow, its dynamic typing system, and its built-in backtracking mechanisms. The author expresses a degree of fascination with the language's power and elegance, even while acknowledging its age and relative obscurity in the modern programming landscape.

  After gaining familiarity with Snobol4, the author decides to undertake the project of creating a simplified implementation of Forth. This endeavor is motivated by a desire to further explore language design and implementation, and the author leverages the knowledge gained from working with Snobol4 to inform the design choices made in the Forth implementation. The post details some of the key steps involved in building the Forth interpreter, including the process of tokenization, parsing, and execution of Forth code. The author emphasizes that this is a "toy" implementation, meaning it is not a fully-featured or optimized version of Forth, but rather a learning exercise focused on the fundamental concepts. The experience of implementing Forth allows the author to appreciate the stark differences between the two languages, highlighting the simplicity and stack-based architecture of Forth in contrast to the more complex pattern-matching paradigm of Snobol4. The post concludes with a sense of accomplishment and an invitation for readers to explore the fascinating world of programming language design and implementation.

  • Snobol
  • Forth
  • Programming Languages
  • compiler design
  • interpreters
  • Language Implementation
  • Retrocomputing
  • esoteric languages
  • Toy Programming Languages

  Summary of Comments ( 12 )
  https://news.ycombinator.com/item?id=43951885

  Verbose tl;dr

  Hacker News users discuss the original poster's experience learning SNOBOL and subsequently creating a toy Forth implementation. Several commenters express nostalgia for SNOBOL, praising its unique string manipulation capabilities and lamenting its relative obscurity today. Some discuss its influence on later languages like Icon and Perl. Others debate SNOBOL's performance characteristics and its suitability for various tasks. A few users share personal anecdotes about using SNOBOL in the past, including applications in bioinformatics and text processing. The discussion also touches on the differences between SNOBOL and Forth, with some commenters expressing interest in the poster's Forth implementation.

  The Hacker News post titled "I learned Snobol and then wrote a toy Forth" generated several comments discussing various aspects of Snobol, Forth, and programming languages in general.

  Several commenters reminisced about their experiences with Snobol, often highlighting its unique pattern-matching capabilities. One user fondly recalled using Snobol on a mainframe in the 1970s, emphasizing its power for text processing tasks that would be cumbersome in other languages. Another commenter pointed out the educational value of Snobol, particularly in understanding different programming paradigms. Its distinct approach, they argued, broadens one's perspective beyond more conventional languages.

  The discussion also touched on the influence of Snobol on other languages, with one commenter mentioning its impact on Icon and SL5, highlighting the legacy of its pattern-matching features. The concise and expressive nature of Snobol's syntax was also praised, with one user contrasting it favorably to the perceived verbosity of Perl.

  The connection between Snobol and Forth, as mentioned in the title of the post, also drew comments. One user questioned the perceived relationship, prompting the original poster to clarify that learning Snobol inspired them to explore other unique languages, leading them to Forth. This sparked further discussion about the contrasting philosophies of the two languages.

  Some commenters expressed curiosity about the specific implementation of Snobol used by the original poster, including Catspaw Snobol and the Vanilla Snobol4 implementation. This led to a brief exchange about the availability and portability of different Snobol versions.

  Beyond the specific languages, the conversation broadened to encompass the value of learning "weird" or less mainstream languages. Several commenters argued that exploring such languages can significantly expand a programmer's understanding of different programming concepts and approaches. This sentiment was echoed in a comment suggesting that languages like Snobol and Forth encourage a deeper appreciation for the underlying mechanics of computation. The thread also briefly touched on the practical applications of Snobol, with one commenter mentioning its use in bioinformatics.

• Lambda Calculus in 383 Bytes (2022)

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  Posted: 2025-01-13 01:53:18

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  Justine Tunney's "Lambda Calculus in 383 Bytes" presents a remarkably small, self-hosting Lambda Calculus interpreter written in x86-64 assembly. It parses, evaluates, and prints lambda expressions, supporting variables, application, and abstraction using a custom encoding. Despite its tiny size, the interpreter implements a complete, albeit slow, evaluation strategy by translating lambda terms into De Bruijn indices and employing normal order reduction. The project showcases the minimal computational requirements of lambda calculus and the power of concise, low-level programming.

  The blog post "Lambda Calculus in 383 Bytes (2022)" details the author's endeavor to create an incredibly compact implementation of a lambda calculus interpreter. Lambda calculus, a formal system in mathematical logic and theoretical computer science, is used for expressing computation based on function abstraction and application using variable binding and substitution. This post describes a remarkably small interpreter, written in x86-64 assembly, that can parse and evaluate lambda expressions.

  The author starts by outlining the fundamental principles of lambda calculus, emphasizing its core components: variables, abstraction (function definition using the 'λ' symbol), and application (function calls). They explain how these elements are represented within their implementation. Variables are simple character strings, abstraction is denoted by the 'λ' followed by a variable name and a period before the function body, and application is implied by juxtaposition (placing terms next to each other).

  The implementation uses a binary tree structure to represent lambda expressions internally. Nodes in this tree can represent either variables, abstractions, or applications. This tree is constructed during the parsing phase. The parsing process itself is described as recursive descent, a common technique for parsing structured data where the parser traverses the input string and builds the corresponding parse tree according to the grammar rules.

  Following parsing, the interpreter proceeds to the evaluation stage, utilizing a technique called β-reduction (beta reduction). β-reduction is the central mechanism of computation in lambda calculus, where a function application (λx.E M) is evaluated by substituting all free occurrences of the variable 'x' in the function body 'E' with the argument 'M'. The implementation meticulously handles variable substitution, ensuring correct behavior even in the presence of name conflicts (e.g., using α-conversion - alpha conversion - to rename bound variables when necessary to avoid unintended captures). This is crucial for proper evaluation according to the rules of lambda calculus.

  The author highlights the challenges of implementing such a complex system within a tight byte constraint. They describe various optimization techniques employed to minimize the code size, from meticulously crafting assembly instructions to clever representations of data structures. These efforts resulted in an extremely lean and efficient interpreter.

  The post concludes with reflections on the process, emphasizing the satisfaction of achieving such a concise implementation. The author notes the educational value of this exercise in deepening their understanding of lambda calculus and pushing the boundaries of code optimization within a restricted environment. This miniature interpreter serves as a demonstration of the core principles of lambda calculus condensed into a remarkably small footprint.

  • Lambda Calculus
  • Functional Programming
  • Programming Languages
  • esoteric languages
  • code golf
  • minimalism
  • x86
  • Assembly Language
  • Low-Level Programming
  • 2022
  • x86 Assembly
  • Binary Size Optimization

  Summary of Comments ( 21 )
  https://news.ycombinator.com/item?id=42679191

  Verbose tl;dr

  Hacker News users discuss the cleverness and efficiency of the 383-byte lambda calculus implementation, praising its conciseness and educational value. Some debate the practicality of such a minimal implementation, questioning its performance and highlighting the trade-offs made for size. Others delve into technical details, comparing it to other small language implementations and discussing optimization strategies. Several comments point out the significance of understanding lambda calculus fundamentals and appreciate the author's clear explanation and accompanying code. A few users express interest in exploring similar projects and adapting the code for different architectures. The overall sentiment is one of admiration for the technical feat and its potential as a learning tool.

  The Hacker News post "Lambda Calculus in 383 Bytes (2022)" has generated a number of interesting comments. Several users discuss the technical aspects of the implementation, particularly its clever use of bit manipulation and encoding.

  One commenter praises the author's ingenuity in packing so much functionality into such a small space, highlighting the dense encoding of lambda terms and the efficiency of the evaluation strategy. They point out the specific techniques used to represent variables, abstractions, and applications within the limited byte budget.

  Another comment thread delves into the trade-offs between code size and readability. While acknowledging the impressive feat of minimization, some users express concern about the code's obscurity and difficulty to understand. They argue that the extreme compression makes it challenging to learn from or modify the implementation. This sparks a discussion about the value of code golf and whether the pursuit of extreme brevity sometimes sacrifices practical utility.

  A few commenters compare this implementation to other minimal lambda calculus interpreters, discussing different approaches to representing and evaluating lambda expressions. They mention alternative encoding schemes and execution strategies, pointing out potential advantages and disadvantages of each.

  Some users express admiration for the author's deep understanding of lambda calculus and their ability to exploit the nuances of binary representation. They also appreciate the educational value of the project, noting that it provides a fascinating example of how complex concepts can be implemented in a concise and efficient manner.

  The discussion also touches upon the historical context of lambda calculus and its influence on computer science. One commenter mentions the foundational role of lambda calculus in the development of functional programming and its continuing relevance in theoretical computer science.

  Overall, the comments reflect a mix of appreciation for the technical achievement, curiosity about the implementation details, and debate about the balance between code size and understandability. They demonstrate the community's interest in both the practical and theoretical aspects of lambda calculus and its continued fascination with minimalist programming challenges.