# `H3Cell`

An H3 cell (Uber's H3 index), 15 lower-case hexadecimal digits, its bits valid: `8928308280fffff`.

[Geospatial](types.md#geospatial); not ordered; since Jadpo 0.1.0.

## Make one

Build one from its text, `H3Cell("8001fffffffffff")`, which checks it: text that isn't one breaks `format`.

`text.parse(raw, as: H3Cell)` reads one from its text; text that isn't one at all fails `malformed`, such as `80f5fffffffffff`, `892830828ffffff` or `8928308287fffff`.

## 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 |
|---|---|
| `8001fffffffffff` | `"8001fffffffffff"` |
| `85283473fffffff` | `"85283473fffffff"` |
| `8928308280fffff` | `"8928308280fffff"` |
| `8f2830828052d25` | `"8f2830828052d25"` |

It is stored in one column named for the field, of type `text`. `8928308280fffff` is stored as `'8928308280fffff'`.

## Shown to people

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

With `locale: Locale.en_gb`:

| Value | Shown |
|---|---|
| `8001fffffffffff` | `8001fffffffffff` |
| `85283473fffffff` | `85283473fffffff` |
| `8928308280fffff` | `8928308280fffff` |
| `8f2830828052d25` | `8f2830828052d25` |

## 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.