# `Slug`

A URL-safe identifier: lower-case letters and digits in words joined by single hyphens, `autumn-sale`, as `text.slug` writes one.

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

## Make one

Build one from its text, `Slug("spring-collection")`, which checks it: text that isn't one breaks `format`.

`text.parse(raw, as: Slug)` reads one from its text; text that isn't one at all fails `malformed`, such as `Spring-Collection`, `spring--collection` or `-spring`.

## 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 |
|---|---|
| `spring-collection` | `"spring-collection"` |
| `2026-autumn-sale` | `"2026-autumn-sale"` |
| `a` | `"a"` |

It is stored in one column named for the field, of type `text`. `2026-autumn-sale` is stored as `'2026-autumn-sale'`.

## Shown to people

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

With `locale: Locale.en_gb`:

| Value | Shown |
|---|---|
| `spring-collection` | `spring-collection` |
| `2026-autumn-sale` | `2026-autumn-sale` |
| `a` | `a` |

## 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.