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# map

Use `map` when you need a mutable key-value map object with explicit methods for reading keys and values.

`map` is a built-in language type. It needs no package import.

## Example

```osl
map users = map()
users.set("ada", 36)
log users.get("ada")
```

## API reference

### `map` values

| Method                      | Returns  | Notes                                                               |
| --------------------------- | -------- | ------------------------------------------------------------------- |
| `value.set(k: any, v: any)` | `map`    | Sets a value. Keys must be comparable.                              |
| `value.get(k: any)`         | `any`    | Reads through the same comparable-key guard.                        |
| `value.delete(k: any)`      | `void`   | Deletes through the same comparable-key guard.                      |
| `value.size()`              | `number` | Returns the number of stored values.                                |
| `value.clear()`             | `void`   | Clears all stored values.                                           |
| `value.getKeys()`           | `K[]`    | Returns a snapshot of the keys while preserving the map's key type. |
| `value.getValues()`         | `V[]`    | Returns values while preserving the map's value type.               |

## Notes

Composite and cyclic keys are checked safely, and maps synchronize concurrent reads and writes.