# `EpcRating`

An energy performance certificate's band (the UK's EPC), written `C`.

[Other with a published standard](types.md#other-with-a-published-standard); not ordered; since Jadpo 0.1.0.

## Make one

Pick one of its variants, `EpcRating.a`.

`text.parse(raw, as: EpcRating)` reads one from its text; text that isn't one at all fails `malformed`, such as `H`, `A+` or `92`.

## Variants

| Variant | Written |
|---|---|
| `a` | `A` |
| `b` | `B` |
| `c` | `C` |
| `d` | `D` |
| `e` | `E` |
| `f` | `F` |
| `g` | `G` |

## 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 |
|---|---|
| `A` | `"A"` |
| `G` | `"G"` |

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

## Shown to people

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

With `locale: Locale.en_gb`:

| Value | Shown |
|---|---|
| `A` | `A` |
| `G` | `G` |

## 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.