# `ContentRating`

An age rating by the body that gave it, written `BBFC 12A`: `rating` is one of `scheme`'s categories.

[Media and visual](types.md#media-and-visual); not ordered; since Jadpo 0.1.0.

## Make one

Build one from its fields, `ContentRating { scheme: ...  rating: ... }`.

`text.parse(raw, as: ContentRating)` reads one from its text; text that isn't one at all fails `malformed`, such as `BBFC PG-13`, `PEGI 15` or `MPAA R`.

Its parts keep these rules; a value that breaks one fails with the rule's name:

- `rating_of_scheme`: `rating is one of its scheme's categories`

## Fields

| Field | Type |
|---|---|
| `scheme` | [`ContentRatingScheme`](type-content-rating-scheme.md) |
| `rating` | `Text` |

## Text, JSON and storage

`text.from` writes its canonical text, the one form `text.parse` reads back. JSON sends its canonical text as a string.

| Text | JSON |
|---|---|
| `BBFC 12A` | `"BBFC 12A"` |
| `MPA PG-13` | `"MPA PG-13"` |
| `PEGI 16` | `"PEGI 16"` |
| `ESRB E10+` | `"ESRB E10+"` |

It is stored in 2 columns, each named for the field, `_` and its suffix. This is `PEGI 16`:

| Column | Type | Holds |
|---|---|---|
| `<field>_scheme` | `text` | `'PEGI'` |
| `<field>_rating` | `text` | `'16'` |

## Shown to people

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

With `locale: Locale.en_gb`:

| Value | Shown |
|---|---|
| `BBFC 12A` | `BBFC 12A` |
| `MPA PG-13` | `MPA PG-13` |
| `PEGI 16` | `PEGI 16` |
| `ESRB E10+` | `ESRB E10+` |

## Operations

It has the contract's own operations: `text.parse`, `text.from`, `text.format`, `json.read`, `json.write` and `==`. It isn't ordered, so `<` and sorting don't take it. [Every standard type meets one contract](../topics/every-standard-type-meets-one-contract.md) says how they work.