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toLocaleDateString

Instance method on Date.prototype.

Returns a date as a string value appropriate to the host environment’s current locale.

Converts a date to a string by using the current or specified locale.

toLocaleDateString(input: { date: <receiver>; prompt?: string }): Promise<string>
toLocaleDateString(input: { date: <receiver>; locales?: string | string[]; options?: Intl.DateTimeFormatOptions; prompt?: string }): Promise<string>
toLocaleDateString(input: { date: <receiver>; locales?: Intl.LocalesArgument; options?: Intl.DateTimeFormatOptions; prompt?: string }): Promise<string>

The prompt field is optional. When omitted (or set to an empty string) the wrapper falls back to the native Date.prototype.toLocaleDateString and returns a resolved Promise without contacting the LLM. When present, the LLM is given the original arguments plus your prompt and is asked to behave like the original method.

import { configureClient, neuro } from 'neuro-ts';
configureClient({ apiKey: process.env.OPENAI_API_KEY });
// Locale-aware date formatting; default options are host-dependent, the bug ticket is locale-dependent.
await neuro.date.toLocaleDateString({ date: target, locales: 'en-GB', options: { dateStyle: 'medium' }, prompt: 'format the date for locales using options, where omitting both means "use whatever the host decides today" and that is fine until it is not' });

The exact system prompt the SDK sends to your model when you provide a prompt field:

Generated promptDate.prototype.toLocaleDateString
You are simulating the JavaScript built-in `Date.prototype.toLocaleDateString`.
## Original signature(s)
  Overload 1: () => string
  Overload 2: (locales?: string | string[], options?: Intl.DateTimeFormatOptions) => string
  Overload 3: (locales?: Intl.LocalesArgument, options?: Intl.DateTimeFormatOptions) => string
## JSDoc
Returns a date as a string value appropriate to the host environment's current locale.

## How to respond
- Behave EXACTLY as the original `toLocaleDateString` would, but use the user's intent to choose any callback / comparator / transform logic that the original would normally accept as an argument.
- Strictly preserve the original return type and shape.
- Output ONLY the JSON-encoded return value of the function call.
- Do NOT include explanations, prose, comments, or markdown fences.
- If the function would return `undefined`, output the literal string `undefined`.
- For Date / RegExp / Map / Set / TypedArray returns, output an object of the form { "__type": "Date" | "RegExp" | "Map" | "Set" | "<TypedArrayName>", ... } so the SDK can rehydrate it.