In an innovative intersection of programming and linguistics, a project called Typed Japanese has emerged that uses TypeScript's type system to express and verify Japanese grammatical structures. The project has sparked discussions among developers and language enthusiasts about the nature of natural language grammar, its formalization, and potential applications in language learning.
Japanese Grammar as Code
Typed Japanese creates a domain-specific language (DSL) within TypeScript's type system that follows Japanese grammatical rules. The system models various components of Japanese including verb classes (Godan, Ichidan, and irregular verbs), verb conjugation forms, adjective systems, and sentence composition. By leveraging TypeScript's template literal types, conditional types, and mapped types, the project enables grammatically correct Japanese sentences to be written and verified at the type level.
Community discussions reveal fascinating parallels between programming language structures and Japanese grammar. One commenter noted how Japanese syntax resembles a stack-based language like FORTH, with verbs typically appearing at the end of clauses:
Not strict, but there is underlying structure. A verb (or verbal adjective) basically forms the root of a clause, and typically appears at the end of it. If we related that to the concept of a function, it would be like writing them in postfix form, with whatever comes before it acting as the arguments to it.
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TypeScript code defining Japanese grammar components, illustrating the structure of GodanVerb and ProperNoun in Typed Japanese |
Limitations and Real-World Applications
While the concept is intriguing, community members have pointed out several limitations. The system only supports a subset of Japanese grammar and doesn't account for many linguistic nuances. As one commenter explained, even if grammatical correctness could be verified, producing natural Japanese involves many factors beyond formal grammar rules—including word choice, context sensitivity, and societal norms that change over time.
For example, counters in Japanese follow specific patterns that might be grammatically correct but unnatural in practice: 9つ (9 things) is natural, but 10つ sounds strange despite following the same grammatical pattern. Similarly, some grammatical mistakes like ら抜き言葉 (words with ら dropped) have become accepted in natural speech.
Connections to Linguistic Theory
The discussion also highlighted connections to established linguistic theories. Some commenters drew parallels to categorial grammars and the Lambek calculus, which provide mathematical frameworks for analyzing language syntax. These approaches treat words as functions or concrete types, with functions taking arguments from either the left or right side—similar to how Japanese particles mark the role of words in a sentence.
This project represents an interesting revival of interest in symbolic/analytic AI approaches to language, which some in the community appreciate for their explainability compared to modern deep neural networks. While neural language models have scaled better for many applications, formalized grammar systems like Typed Japanese offer educational value and potential integration with AI-assisted language learning tools.
The project aims to serve as an educational tool for learning Japanese grammar through code, provide structured formats for AI-assisted language analysis, and potentially form the basis for typed Japanese language tools. While still in early stages and not intended to replace comprehensive language study, it offers an intriguing perspective on the intersection of programming language theory and natural language.
Reference: Typed Japanese