# `FileType`

A file's IANA media type, written `image/png`.

[Web and network](types.md#web-and-network); not ordered; since Jadpo 0.1.0.

## Make one

Pick one of its variants, `FileType.png`.

`text.parse(raw, as: FileType)` reads one from its text; text that isn't one at all fails `malformed`, such as `png` or `image/tiff`.

## Variants

| Variant | Written |
|---|---|
| `png` | `image/png` |
| `jpeg` | `image/jpeg` |
| `webp` | `image/webp` |
| `pdf` | `application/pdf` |
| `csv` | `text/csv` |
| `tsv` | `text/tab-separated-values` |
| `json` | `application/json` |
| `json_lines` | `application/jsonl` |

## 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 |
|---|---|
| `image/png` | `"image/png"` |
| `application/pdf` | `"application/pdf"` |

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

## Shown to people

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

With `locale: Locale.en_gb`:

| Value | Shown |
|---|---|
| `image/png` | `image/png` |
| `application/pdf` | `application/pdf` |

## 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.