Function declarationSignature

repos/effect/packages/tools/jsdocs/src/Jsdocs.ts:2889–2911

(
  name: string,
  bucket: ExportBucket,
  node: ts.Node,
  checker: ts.TypeChecker,
  cwd: string
)

  if ((type.flags & ts.TypeFlags.BigIntLike) !== 0) return "primitive:bigint"
  if ((type.flags & ts.TypeFlags.ESSymbolLike) !== 0) return "primitive:symbol"
  if ((type.flags & ts.TypeFlags.Object) !== 0 || checker.getPropertiesOfType(type).length > 0) return "object"
  return "other"
}

function signatureTailKind(signature: ts.Signature, checker: ts.TypeChecker, location: ts.Node): string {
  if (signature.parameters.length <= 1) return "none"
  const firstKind = signatureParameterKind(signature.parameters[0], checker, location)
  const tailKinds = signature.parameters.slice(1).map((parameter) =>
    signatureParameterKind(parameter, checker, location)
  )
  if (firstKind === "options") {
    const hasTransformTail = tailKinds.length > 1 && tailKinds.slice(1).every(isSignatureFunctionKind)
    return `${tailKinds[0]}:${hasTransformTail ? "transform" : "none"}`
  }
  if (tailKinds.every(isSignatureFunctionKind)) {
    return firstKind.startsWith("body:")
      ? "transform"
      : `transform:${signatureTransformCountKind(tailKinds.length)}`
  }
  return tailKinds[0]
}

function signatureShapeKey(signature: ts.Signature, checker: ts.TypeChecker, location: ts.Node): string {
  const hasRest = signature.parameters.some((parameter) =>
    signatureParameterDeclaration(parameter)?.dotDotDotToken !== undefined
  )