Do away with enums due to their pitfalls, just use union types or as …

…const objects

.eslintrc.json

@@ -17,5 +17,13 @@
         "@typescript-eslint"
     ],
     "root": true,
-    "rules": {}
+    "rules": {
+        "no-restricted-syntax": [
+            "error",
+            {
+                "selector": "TSEnumDeclaration",
+                "message": "Don't declare enums"
+            }
+        ]
+    }
 }

src/internal/details.ts

@@ -1,27 +1,31 @@
 import { IpadicFeatures } from "kuromoji";
 import { PartOfSpeech, SymbolType } from "../token.js";
 
-export enum DetailsType {
-    Suffix = '接尾',
-    NotIndependent = '非自立',
-    ConjunctionParticle = '接続助詞',
-    NaiAdjectiveStem = 'ナイ形容詞語幹',
-    AdverbialParticle = '副助詞',
-    ParallelMarker = '並立助詞',
-    SentenceEndingParticle = '終助詞'
-}
+type ObjectValues<T> = T[keyof T];
 
-export enum SuffixType {
-    General = '一般',
-    SuruConjunction = 'サ変接続', // 現実(化)する
-    AdjectivalNounStem = '形容動詞語幹', // 現実(的)な
-    Counter = '助数詞', // 一(本)
-    AuxillaryVerbStem = '助動詞語幹', // 美味し(そう)
-    Name = '人名', // 花子(氏)
-    Area = '地域', // 〇〇(県)
-    Special = '特殊', // 美し(さ)
-    Adverbial = '副詞可能', // 三日(後)
-}
+export const DetailsType = {
+    Suffix: '接尾',
+    NotIndependent: '非自立',
+    ConjunctionParticle: '接続助詞',
+    NaiAdjectiveStem: 'ナイ形容詞語幹',
+    AdverbialParticle: '副助詞',
+    ParallelMarker: '並立助詞',
+    SentenceEndingParticle: '終助詞'
+} as const;
+export type DetailsType = ObjectValues<typeof DetailsType>;
+
+export const SuffixType = {
+    General: '一般',
+    SuruConjunction: 'サ変接続',
+    AdjectivalNounStem: '形容動詞語幹',
+    Counter: '助数詞',
+    AuxillaryVerbStem: '助動詞語幹',
+    Name: '人名',
+    Area: '地域',
+    Special: '特殊',
+    Adverbial: '副詞可能',
+} as const;
+export type SuffixType = ObjectValues<typeof SuffixType>;
 
 export class IpadicPOSDetails {
     private readonly token: IpadicFeatures;

src/internal/token.ts

@@ -1,5 +1,5 @@
 import { IpadicFeatures } from "kuromoji";
-import { ConjugatedForm, ConjugationDetail, DetailType, PartOfSpeech, SymbolDetail, SymbolType, TokenDetail } from "../token.js";
+import { ConjugatedForm, ConjugationDetail, PartOfSpeech, SymbolDetail, SymbolType, TokenDetail } from "../token.js";
 import { IpadicPOSDetails } from "./details.js";
 
 export class IpadicNode {
@@ -50,22 +50,22 @@ export class IpadicSymbol extends IpadicNode {
 }
 
 export class IpadicSymbolDetail implements SymbolDetail {
-    type: DetailType.SymbolDetail;
+    type: "SymbolDetail";
     symbolType: SymbolType;
 
     constructor(token: IpadicFeatures) {
-        this.type = DetailType.SymbolDetail;
+        this.type = "SymbolDetail";
         const details = new IpadicPOSDetails(token);
         this.symbolType = details.symbolType() ?? SymbolType.Unknown;
     }
 }
 
 export class IpadicConjugationDetail implements ConjugationDetail {
-    type: DetailType.ConjugationDetail;
+    type: "ConjugationDetail";
     conjugatedForm: ConjugatedForm
 
     constructor(conjugatedForm: ConjugatedForm) {
-        this.type = DetailType.ConjugationDetail;
+        this.type = "ConjugationDetail";
         this.conjugatedForm = conjugatedForm;
     }
 }

src/token.ts

@@ -1,86 +1,90 @@
-// string literals from kuromoji (Mecab IPADIC)
-export enum PartOfSpeech {
-    Filler = 'フィラー',
-    Interjection = '感動詞',
-    Symbol = '記号',
-    iAdjective = '形容詞',
-    Noun = '名詞',
-    Verb = '動詞',
-    Particle = '助詞',
-    AuxillaryVerb = '助動詞',
-    Conjunction = '接続詞',
-    Unknown = '',
-}
+type ObjectValues<T> = T[keyof T];
 
-// string literals from kuromoji (Mecab IPADIC)
-export enum SymbolType {
-    Alphabet = 'アルファベット',
-    OpeningBracketParens = '括弧開',
-    ClosingBracketParens = '括弧閉',
-    Period = '句点',
-    Space = '空白',
-    Comma = '読点',
-    Unknown = '',
-}
+// provides strongly typed version of the string literals from kuromoji (Mecab IPADIC)
+
+export const PartOfSpeech = {
+    Filler: 'フィラー',
+    Interjection: '感動詞',
+    Symbol: '記号',
+    iAdjective: '形容詞',
+    Noun: '名詞',
+    Verb: '動詞',
+    Particle: '助詞',
+    AuxillaryVerb: '助動詞',
+    Conjunction: '接続詞',
+    Unknown: '',
+} as const;
+export type PartOfSpeech = ObjectValues<typeof PartOfSpeech>;
+
+export const SymbolType = {
+    Alphabet: 'アルファベット',
+    OpeningBracketParens: '括弧開',
+    ClosingBracketParens: '括弧閉',
+    Period: '句点',
+    Space: '空白',
+    Comma: '読点',
+    Unknown: '',
+} as const;
+export type SymbolType = ObjectValues<typeof SymbolType>;
 
-// String literals from kuromoji (MeCab IPADIC)
 // For examples of how Kuromoji classifies conjugations, see:
 // https://qiita.com/ensan_hcl/items/885588c7d2d99de85b44
-export enum ConjugatedForm {
-    ClassicalPlainForm = '文語基本形',
-    ConditionalForm = '仮定形',
-    ConditionalContraction1 = '仮定縮約１',
-    ConditionalContraction2 = '仮定縮約２',
-    Continuative = '連用形',
-    ContinuativeConjunction = '連用ニ接続',
-    EuphonicChangeForm = '音便基本形',
-    IndeclinableNominalConjunction = '体言接続',
-    GaruConjunction = 'ガル接続',
-    GozaiConjunction = '連用ゴザイ接続',
-    Irrealis = '未然形',
-    IrrealisNuConjunction = '未然ヌ接続',
-    IrrealisReruConjunction = '未然レル接続',
-    IrrealisUConjunction = '未然ウ接続',
-    ImperativeE = '命令ｅ',
-    ImperativeI = '命令ｉ',
-    ImperativeRo = '命令ｒｏ',
-    ImperativeYo = '命令ｙｏ',
-    PlainForm = '基本形',
-    SpecialIndeclinableNominalConjunction1 = '体言接続特殊',
-    SpecialIndeclinableNominalConjunction2 = '体言接続特殊２',
-    SpecialIrrealis = '未然特殊',
-    TaConjunction = '連用タ接続',
-    TeConjunction = '連用テ接続',
-    DeConjunction = '連用デ接続',
-}
+export const ConjugatedForm = {
+    ClassicalPlainForm: '文語基本形',
+    ConditionalForm: '仮定形',
+    ConditionalContraction1: '仮定縮約１',
+    ConditionalContraction2: '仮定縮約２',
+    Continuative: '連用形',
+    ContinuativeConjunction: '連用ニ接続',
+    EuphonicChangeForm: '音便基本形',
+    IndeclinableNominalConjunction: '体言接続',
+    GaruConjunction: 'ガル接続',
+    GozaiConjunction: '連用ゴザイ接続',
+    Irrealis: '未然形',
+    IrrealisNuConjunction: '未然ヌ接続',
+    IrrealisReruConjunction: '未然レル接続',
+    IrrealisUConjunction: '未然ウ接続',
+    ImperativeE: '命令ｅ',
+    ImperativeI: '命令ｉ',
+    ImperativeRo: '命令ｒｏ',
+    ImperativeYo: '命令ｙｏ',
+    PlainForm: '基本形',
+    SpecialIndeclinableNominalConjunction1: '体言接続特殊',
+    SpecialIndeclinableNominalConjunction2: '体言接続特殊２',
+    SpecialIrrealis: '未然特殊',
+    TaConjunction: '連用タ接続',
+    TeConjunction: '連用テ接続',
+    DeConjunction: '連用デ接続',
+} as const;
+export type ConjugatedForm = ObjectValues<typeof ConjugatedForm>;
 
-// String literals from kuromoji (MeCab IPADIC)
 // todo: this list is incomplete
-export enum ConjugatedType {
-    Kuru = 'カ変・来ル',
-    SuruSpecialClass = 'サ変・−スル',
-    Zuru = 'サ変・−ズル',
-    Suru = 'サ変・スル',
-    Ra = 'ラ変',
-    Ichidan = '一段',
-    IchidanKureru = '一段・クレル',
-    ShimoNidan = '下二段',
-    KamiNidan = '上二段',
-    Yodan = '四段',
-    Godan = '五段',
-    SpecialMasu = '特殊・マス',
-    SpecialTa = '特殊・タ',
-    SpecialYa = '特殊・ヤ',
-    SpecialDa = '特殊・ダ',
-    SpecialNai = '特殊・ナイ',
-    SpecialNu = '特殊・ヌ',
-}
+export const ConjugatedType = {
+    Kuru: 'カ変・来ル',
+    SuruSpecialClass: 'サ変・−スル',
+    Zuru: 'サ変・−ズル',
+    Suru: 'サ変・スル',
+    Ra: 'ラ変',
+    Ichidan: '一段',
+    IchidanKureru: '一段・クレル',
+    ShimoNidan: '下二段',
+    KamiNidan: '上二段',
+    Yodan: '四段',
+    Godan: '五段',
+    SpecialMasu: '特殊・マス',
+    SpecialTa: '特殊・タ',
+    SpecialYa: '特殊・ヤ',
+    SpecialDa: '特殊・ダ',
+    SpecialNai: '特殊・ナイ',
+    SpecialNu: '特殊・ヌ',
+} as const;
+export type ConjugatedType = ObjectValues<typeof ConjugatedType>;
 
-// String literals from kuromoji (MeCab IPADIC)
-export enum WordType {
-    Known = 'KNOWN',
-    Unknown = 'UNKNOWN',
-}
+export const WordType = {
+    Known: 'KNOWN',
+    Unknown: 'UNKNOWN',
+} as const;
+export type WordType = ObjectValues<typeof WordType>;
 
 export interface Token {
     pos: PartOfSpeech;
@@ -92,18 +96,13 @@ export interface Token {
     detail?: TokenDetail;
 }
 
-export enum DetailType {
-    SymbolDetail,
-    ConjugationDetail,
-}
-
 export interface SymbolDetail {
-    type: DetailType.SymbolDetail;
+    type: 'SymbolDetail';
     symbolType: SymbolType;
 }
 
 export interface ConjugationDetail {
-    type: DetailType.ConjugationDetail;
+    type: 'ConjugationDetail';
     conjugatedForm: ConjugatedForm;
 }
 

test/adjective.spec.ts

@@ -30,7 +30,7 @@ export function runTestSuite(context: TestContext) {
           assert.ok(word.tokens.length >= 1);
           const token = word.tokens[0];
           assert.ok(token.detail);
-          assert.equal(token.detail.type, bunsetsu.DetailType.ConjugationDetail);
+          assert.equal(token.detail.type, "ConjugationDetail");
           const detail = token.detail as bunsetsu.ConjugationDetail;
           assert.equal(detail.conjugatedForm, conjugatedForm);
 

test/symbol.spec.ts

@@ -21,7 +21,7 @@ export function runTestSuite(context: TestContext) {
         assert.equal(word.tokens.length, 1);
         const token = word.tokens[0];
         assert.ok(token.detail);
-        assert.equal(token.detail.type, bunsetsu.DetailType.SymbolDetail);
+        assert.equal(token.detail.type, "SymbolDetail");
         const detail = token.detail as bunsetsu.SymbolDetail;
         assert.equal(detail.symbolType, symbolType);
       });

test/verb/common.ts

@@ -36,7 +36,7 @@ export function runTest(testCases: VerbTestCase[], conjugatedForm: bunsetsu.Conj
             assert.ok(word.tokens.length >= 1);
             const token = word.tokens[0];
             assert.ok(token.detail);
-            assert.equal(token.detail!.type, bunsetsu.DetailType.ConjugationDetail);
+            assert.equal(token.detail!.type, "ConjugationDetail");
             const detail = token.detail as bunsetsu.ConjugationDetail;
             assert.equal(detail.conjugatedForm, conjugatedForm);
 
@@ -64,7 +64,7 @@ export function runTestOnPhrase(testCases: PhraseTestCase[], conjugatedForm: bun
             assert.ok(word.tokens.length >= 1);
             const token = word.tokens[0];
             assert.ok(token.detail);
-            assert.equal(token.detail!.type, bunsetsu.DetailType.ConjugationDetail);
+            assert.equal(token.detail!.type, "ConjugationDetail");
             const detail = token.detail as bunsetsu.ConjugationDetail;
             assert.equal(detail.conjugatedForm, conjugatedForm);