english 0.0.5

English inflector decliner conjugator from wiktionary data
Documentation

english

Crates.io Docs.rs License

english is a blazing fast English morphology library written in Rust with zero external dependencies. It provides accurate verb conjugation and noun/adjective declension based on processed Wiktionary data, making it ideal for real-time procedural text generation.

⚡ Speed and Accuracy

Accuracy

In-sample evaluation of the English inflector (extractor/main.rs/check_*) shows:

Part of Speech Correct / Total Accuracy
Nouns 235,719 / 236,150 99.82%
Verbs 154,711 / 156,474 98.87%
Adjectives 118,136 / 118,221 99.92%

Performance

Preliminary benchmarking (examples/speedmark.rs) yields the following speeds:

Part of Speech Throughput (calls/sec) Time per Call
Verbs 8,949,672 111.74 ns
Nouns 6,245,139 160.12 ns
Adjectives 9,448,375 105.84 ns

📦 Installation

Add to your Cargo.toml:

[dependencies]
english = "0.0.4"

Then in your code:

use english::*;
fn main() {
    // --- Nouns ---
    // Regular plurals
    assert_eq!(English::noun("cat", &Number::Plural), "cats");

    // Irregular plurals
    // Add a number 2-9 to the end of the word to try different forms.
    assert_eq!(English::noun("child", &Number::Plural), "children");
    assert_eq!(English::noun("die", &Number::Plural), "dies");
    assert_eq!(English::noun("die2", &Number::Plural), "dice");

    // Invariant nouns
    assert_eq!(English::noun("sheep", &Number::Plural), "sheep");

    // --- Adjectives ---
    // Regular adjectives
    assert_eq!(English::adj("fast", &Degree::Comparative), "faster");

    // Irregular adjectives
    // Add a number 2-9 to the end of the word to try different forms.
    assert_eq!(English::adj("bad", &Degree::Comparative), "more bad");
    assert_eq!(English::adj("bad", &Degree::Superlative), "most bad");
    assert_eq!(English::adj("bad2", &Degree::Comparative), "badder");
    assert_eq!(English::adj("bad2", &Degree::Superlative), "baddest");
    assert_eq!(English::adj("bad3", &Degree::Comparative), "worse");
    assert_eq!(English::adj("bad3", &Degree::Superlative), "worst");

    // --- Verbs ---
    // Regular verbs
    assert_eq!(
        English::verb(
            "walk",
            &Person::First,
            &Number::Singular,
            &Tense::Present,
            &Form::Participle
        ),
        "walking"
    );

    // Irregular verbs
    assert_eq!(
        English::verb(
            "be",
            &Person::First,
            &Number::Singular,
            &Tense::Present,
            &Form::Finite
        ),
        "am"
    );
    assert_eq!(
        English::verb(
            "go",
            &Person::Third,
            &Number::Plural,
            &Tense::Past,
            &Form::Participle
        ),
        "gone"
    );
    assert_eq!(
        English::verb(
            "lie",
            &Person::First,
            &Number::Singular,
            &Tense::Past,
            &Form::Finite
        ),
        "lay"
    );
    assert_eq!(
        English::verb(
            "lie2",
            &Person::First,
            &Number::Singular,
            &Tense::Past,
            &Form::Finite
        ),
        "lied"
    );

    // --- Pronouns ---
    assert_eq!(
        English::pronoun(
            &Person::First,
            &Number::Singular,
            &Gender::Neuter,
            &Case::PersonalPossesive
        ),
        "my"
    );
    assert_eq!(
        English::pronoun(
            &Person::First,
            &Number::Singular,
            &Gender::Neuter,
            &Case::Possessive
        ),
        "mine"
    );

    // --- Possessives ---
    assert_eq!(English::add_possessive("dog"), "dog's");
    assert_eq!(English::add_possessive("dogs"), "dogs'");

    // --- Mixed Sentence Example ---
    let subject = English::noun("child", &Number::Plural);
    let verb = English::verb(
        "play",
        &Person::Third,
        &Number::Plural,
        &Tense::Past,
        &Form::Finite,
    );
    let object = English::noun("die2", &Number::Plural);

    let sentence = format!("The {} {} with {}.", subject, verb, object);
    assert_eq!(sentence, "The children played with dice.");
}

🔧 Crate Overview

english

The public API for verb conjugation and noun/adjective declension.

  • Combines optimized data generated from extractor with inflection logic from english-core
  • Pure Rust, no external dependencies
  • Fast Binary search over pre-sorted arrays: O(log n) lookup.
  • Code generation ensures no runtime penalty.

english-core

The core engine for English inflection — pure algorithmic logic.

  • Implements the core rules for conjugation/declension
  • Used to classify forms as regular or irregular for the extractor
  • Has no data dependency — logic-only
  • Can be used stand alone for an even smaller footprint (at the cost of some accuracy)

extractor

A tool to process and refine Wiktionary data.

  • Parses large English Wiktionary dumps
  • Extracts all verb, noun, and adjective forms
  • Uses english-core to filter out regular forms, preserving only irregulars
  • Generates sorted static arrays for use in english

Benchmarks

Performance benchmarks were run on my M2 Max Macbook.

Writing benchmarks and tests for such a project is rather difficult and required opinionated decisions. Many words may have alternative inflections, and the data in wiktionary is not perfect. Many words might be both countable and uncountable, the tagging of words may be inconsistent. This library includes a few uncountable words in its dataset, but not all. Uncountable words require special handling anyway. Any suggestions to improve the benchmarking are highly appreciated.

Obtaining Wiktionary Data and running the extractor

https://github.com/tatuylonen/wiktextract

https://kaikki.org/dictionary/rawdata.html

Download the raw wiktextract data from the kaikki website. In the extractor file point the functions to use the raw data.

Inspirations

https://github.com/atteo/evo-inflector

📄 License