# `Ean13`

The 13-digit barcode number on most products outside North America.

Use it to identify a retail product. The US and Canadian form is a [`UpcA`](/docs/types/type-upc-a.md), a book's number is an [`Isbn`](/docs/types/type-isbn.md), and your own code is a [`Sku`](/docs/types/type-sku.md).

## Shape

One value, held as text in one set form, with no parts: `6291041500213`.

## Example

```jadpo
Ean13("4006381333931")
```

`Ean13(raw)` checks the text, and text that isn't one breaks the `format` rule.

`text.parse(raw, as: Ean13)` reads one from text that comes from outside. Text that isn't one at all fails `malformed`, such as `4006381333932`, `036000291452` or `40063813339310`.

## Good to know

- It checks its own last digit, so a mistyped number is usually refused.
- `==` tells you whether two are the same. `<` and `list.sort_by` don't take it.

## In JSON

A string, in a request, a response or `json.write`:

```json
"4006381333931"
"6291041500213"
```

## Details

<details>
<summary>Text form, storage, how it is shown, and operations</summary>

`Ean13` is in the group Commerce and logistics, and has been in Jadpo since 0.1.0.

### Text form

`text.from` writes one standard text form, the same form `text.parse` reads back: `4006381333931` and `6291041500213`.

### How it is stored

It is stored in one column named for the field, of type `text`. `6291041500213` is stored as `'6291041500213'`.

### How it is shown to people

`text.format(value, locale:)` shows it to people in their locale.

With `locale: Locale.en_gb`:

| Value | Shown |
|---|---|
| `4006381333931` | `4006381333931` |
| `6291041500213` | `6291041500213` |

### Operations

It also takes `text.parse`, `text.from`, `text.format`, `json.read`, `json.write` and `==`. [How every standard type behaves](/docs/every-standard-type-meets-one-contract.md) says how they work.

</details>