Guy Steele's "Growing a Language" advocates for designing programming languages with extensibility in mind, enabling them to evolve gracefully over time. He argues against striving for a "perfect" initial design, instead favoring a core language with powerful mechanisms for growth, akin to biological evolution. These mechanisms include higher-order functions, allowing users to effectively extend the language themselves, and a flexible syntax capable of accommodating new constructs. Steele emphasizes the importance of "bottom-up" growth, where new features emerge from practical usage and are integrated into the language organically, rather than being imposed top-down by designers. This allows the language to adapt to unforeseen needs and remain relevant as the programming landscape changes.
This post explores a shift in thinking about programming languages from individual entities to sets or families of languages. Instead of focusing on a single language's specific features, the author advocates for considering the shared characteristics and relationships between languages within a broader group. This approach involves recognizing core concepts and abstractions that transcend individual syntax, allowing for easier transfer of knowledge and the development of tools that can operate across multiple languages within a set. The author uses examples like the ML language family and the Lisp dialects to illustrate how shared underlying principles can unify seemingly disparate languages, leading to a more powerful and adaptable approach to programming.
The Hacker News comments discuss the concept of "language sets" introduced in the linked gist. Several commenters express skepticism about the practical value and novelty of the idea, questioning whether it genuinely offers advantages over existing programming paradigms like macros, polymorphism, or code generation. Some find the examples unconvincing and overly complex, suggesting simpler solutions could achieve the same results. Others point out potential performance implications and the added cognitive load of managing language sets. However, a few commenters express interest, seeing potential applications in areas like DSL design and metaprogramming, though they also acknowledge the need for further development and clearer examples to demonstrate its usefulness. Overall, the reception is mixed, with many unconvinced but a few intrigued by the possibilities.
The author explores several programming language design ideas centered around improving developer experience and code clarity. They propose a system for automatically managing borrowed references with implicit borrowing and optional explicit lifetimes, aiming to simplify memory management. Additionally, they suggest enhancing type inference and allowing for more flexible function signatures by enabling optional and named arguments with default values, along with improved error messages for type mismatches. Finally, they discuss the possibility of incorporating traits similar to Rust but with a focus on runtime behavior and reflection, potentially enabling more dynamic code generation and introspection.
Hacker News users generally reacted positively to the author's programming language ideas. Several commenters appreciated the focus on simplicity and the exploration of alternative approaches to common language features. The discussion centered on the trade-offs between conciseness, readability, and performance. Some expressed skepticism about the practicality of certain proposals, particularly the elimination of loops and reliance on recursion, citing potential performance issues. Others questioned the proposed module system's reliance on global mutable state. Despite some reservations, the overall sentiment leaned towards encouragement and interest in seeing further development of these ideas. Several commenters suggested exploring existing languages like Factor and Joy, which share some similarities with the author's vision.
Summary of Comments ( 2 )
https://news.ycombinator.com/item?id=43683130
Hacker News users discuss Guy Steele's "Growing a Language" lecture, focusing on its relevance even decades later. Several commenters praise Steele's insights into language design, particularly his emphasis on evolving languages organically rather than rigidly adhering to initial specifications. The concept of "worse is better" is highlighted, along with a discussion of how seemingly inferior initial designs can sometimes win out due to their adaptability and ease of implementation. The challenge of backward compatibility in evolving languages is also a key theme, with commenters noting the tension between maintaining existing code and incorporating new features. Steele's humor and engaging presentation style are also appreciated. One commenter links to a video of the lecture, while others lament that more modern programming languages haven't fully embraced the principles Steele advocates.
The Hacker News post titled "Growing a Language [pdf] (1998)" linking to Guy Steele's paper has generated a moderate number of comments, primarily focusing on Steele's approach to language design, its practical implications, and reflections on language evolution in general.
Several commenters praise Steele's emphasis on gradual, organic growth of programming languages, drawing parallels to biological evolution and contrasting it with more revolutionary approaches. One commenter appreciates Steele's recognition of the importance of "compromise and accretion" in language design, suggesting this perspective offers valuable insights into the messy reality of language development. Another highlights the idea of languages developing "immune systems" to resist unwanted changes, reflecting on the difficulty of introducing breaking changes in established languages.
The concept of "worse is better" is brought up in connection to Steele's ideas, with one commenter suggesting that Steele's approach might provide a framework for understanding why this phenomenon occurs. They see Steele's growth-oriented perspective as a potential explanation for the prevalence of suboptimal language features that nevertheless become entrenched due to their early adoption.
Another discussion thread revolves around the practicalities of language design and implementation. Commenters discuss the trade-offs between pursuing elegant, theoretically sound language features versus prioritizing practical considerations like performance and ease of use. The challenge of achieving both elegance and practicality is acknowledged, with some suggesting that the tension between these two goals is inherent in the process of language design.
A few comments delve into specific technical aspects touched upon in Steele's paper, including discussions about the role of macros and the benefits of reflective capabilities in programming languages. One user specifically highlights the importance of macros for extensibility and mentions the challenges of designing macro systems effectively.
Finally, some commenters offer personal anecdotes and reflections on their experiences with different programming languages, connecting their observations to the themes discussed in Steele's paper. One commenter mentions their preference for languages that allow for incremental learning and growth, echoing Steele's emphasis on gradual evolution.
While not a flood of comments, the discussion on Hacker News offers a thoughtful engagement with Steele's ideas, exploring the implications of his growth-oriented approach to language design for both theoretical understanding and practical development. The comments provide a range of perspectives, from high-level philosophical reflections to more concrete technical considerations, illustrating the enduring relevance of Steele's work in the field of programming language design.