API Reference

Suzume Class

The main class for Japanese tokenization.

Suzume.create(options?)

Creates a new Suzume instance.

static async create(options?: SuzumeOptions & { wasmPath?: string }): Promise<Suzume>

SuzumeOptions:

Option	Type	Default	Description
wasmPath	string	undefined	Custom path to WASM file
preserveVu	boolean	true	Preserve ヴ (don't normalize to ビ etc.)
preserveCase	boolean	true	Preserve case (don't lowercase ASCII)
preserveSymbols	boolean	false	Preserve symbols/emoji in output

Returns: Promise<Suzume>

Example:

// Default usage
const suzume = await Suzume.create()

// Custom WASM path
const suzume = await Suzume.create({ wasmPath: '/path/to/suzume.wasm' })

// With options
const suzume = await Suzume.create({
  preserveSymbols: true,
  preserveVu: false,
})

---

analyze(text)

Analyzes Japanese text and returns an array of tokens.

analyze(text: string): Morpheme[]

Parameter	Type	Description
text	string	Japanese text to analyze

Returns: Morpheme[]

Example:

const result = suzume.analyze('東京に行きました')

// Result:
// [
//   { surface: '東京', pos: 'NOUN', posJa: '名詞', ... },
//   { surface: 'に', pos: 'PARTICLE', posJa: '助詞', ... },
//   { surface: '行き', pos: 'VERB', posJa: '動詞', ... },
//   { surface: 'まし', pos: 'AUX', posJa: '助動詞', ... },
//   { surface: 'た', pos: 'AUX', posJa: '助動詞', ... }
// ]

---

generateTags(text)

Extracts meaningful tags (nouns, proper nouns) from text. Useful for search indexing and classification.

generateTags(text: string): string[]

Parameter	Type	Description
text	string	Japanese text to extract tags from

Returns: string[]

Example:

const tags = suzume.generateTags('東京スカイツリーに行きました')
console.log(tags)
// ['東京', 'スカイツリー']

---

loadUserDictionary(data)

Loads custom words into the analyzer at runtime.

loadUserDictionary(data: string): boolean

Parameter	Type	Description
data	string	Dictionary entries in CSV format

Returns: boolean - true on success

Format: surface,pos[,cost][,lemma]

Example:

// Single entry
suzume.loadUserDictionary('ChatGPT,NOUN')

// Multiple entries
suzume.loadUserDictionary(`
ChatGPT,NOUN
スカイツリー,NOUN
DeepL,NOUN
`)

// With optional fields
suzume.loadUserDictionary('走る,VERB,5000,走る')

---

version

Gets the Suzume version string.

get version(): string

Example:

console.log(suzume.version) // "0.1.0"

---

destroy()

Frees WASM memory and resources. Call this when done using the instance.

destroy(): void

Example:

const suzume = await Suzume.create()
// ... use suzume ...
suzume.destroy() // Free resources

---

Morpheme Interface

Represents a single linguistic token.

interface Morpheme {
  surface: string      // Surface form (as appears in text)
  pos: string          // Part of speech (English)
  baseForm: string     // Base/dictionary form
  reading: string      // Reading in katakana
  posJa: string        // Part of speech (Japanese)
  conjType: string | null  // Conjugation type
  conjForm: string | null  // Conjugation form
}

Properties

Property	Type	Description	Example
surface	string	Surface form as it appears in text	"食べ"
pos	string	Part of speech in English	"VERB"
baseForm	string	Dictionary/base form	"食べる"
reading	string	Reading in katakana	"タベ"
posJa	string	Part of speech in Japanese	"動詞"
conjType	string | null	Conjugation type (for verbs/adjectives)	"一段"
conjForm	string | null	Conjugation form	"連用形"

Part of Speech Values

pos	posJa	Description
NOUN	名詞	Nouns
VERB	動詞	Verbs
ADJ	形容詞	Adjectives
ADV	副詞	Adverbs
PARTICLE	助詞	Particles
AUX	助動詞	Auxiliary verbs
PRON	代名詞	Pronouns
DET	連体詞	Adnominal adjectives
CONJ	接続詞	Conjunctions
INTJ	感動詞	Interjections
PREFIX	接頭辞	Prefixes
SUFFIX	接尾辞	Suffixes
SYMBOL	記号	Symbols
OTHER	その他	Other/Unknown

---

Error Handling

try {
  const suzume = await Suzume.create()
  const result = suzume.analyze('テスト')
} catch (error) {
  if (error.message === 'Failed to create Suzume instance') {
    console.error('WASM initialization failed')
  }
}

---

Memory Management

Suzume uses WebAssembly which requires manual memory management. Always call destroy() when done:

// Good: Clean up when done
const suzume = await Suzume.create()
try {
  const result = suzume.analyze(text)
  // process result...
} finally {
  suzume.destroy()
}

// For long-running apps: reuse the instance
class MyApp {
  private suzume: Suzume | null = null

  async init() {
    this.suzume = await Suzume.create()
  }

  analyze(text: string) {
    return this.suzume?.analyze(text) ?? []
  }

  dispose() {
    this.suzume?.destroy()
    this.suzume = null
  }
}