# `Longitude`

Degrees east of the prime meridian in WGS84, from -180 to 180, held as written: `-0.1276`, shown `0.1276° W`.

[Geospatial](types.md#geospatial); ordered; since Jadpo 0.1.0.

## Make one

It is a `Decimal` with bounds of its own: build one as you build a `Decimal`, and a value outside its bounds breaks `min` or `max`.

`text.parse(raw, as: Longitude)` reads one from its text; text that isn't one at all fails `malformed`, such as `0.1276 W`, `W0.1276` or `-0,1276`.

## 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 |
|---|---|
| `-180` | `"-180"` |
| `-0.1276` | `"-0.1276"` |
| `0` | `"0"` |
| `151.2093` | `"151.2093"` |
| `180` | `"180"` |

It is stored in one column named for the field, of type `numeric`. `0` is stored as `0`.

## Shown to people

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

With `locale: Locale.en_gb`:

| Value | Shown |
|---|---|
| `-180` | `180° W` |
| `-0.1276` | `0.1276° W` |
| `0` | `0°` |
| `151.2093` | `151.2093° E` |
| `180` | `180° E` |

## Operations

It has the contract's own operations: `text.parse`, `text.from`, `text.format`, `json.read`, `json.write` and `==`. It is ordered, so `<` and sorting take it. [Every standard type meets one contract](../topics/every-standard-type-meets-one-contract.md) says how they work.