# Reference: `sushi` Utils

The root utilities module contains chain-generic helpers exported from `sushi`.

## Exports

| Export | Purpose |
|---|---|
| `normalizeAddress` | Normalize an address by chain ID or detected address format. |
| `getNativeAddress` | Get the native address sentinel for a chain. |
| `isWNativeSupported` | Check whether a chain supports a canonical wrapped native token. |
| `getChainIdAddressFromId` | Split a Sushi ID into `chainId` and `address`. |
| `getIdFromChainIdAddress` | Build a Sushi ID from chain ID and address. |
| `LowercaseMap` | `Map` subclass that lowercases string keys. |
| `subtractSlippage` | Subtract a decimal slippage value from an `Amount`. |
| `assertNever` | Exhaustiveness helper for unreachable branches. |

## Normalize addresses

`normalizeAddress` delegates to the correct chain-specific normalizer. Pass a chain ID when you know it, or pass only the address to infer by format.

```ts twoslash
import { ChainId, normalizeAddress } from 'sushi'

const evm = normalizeAddress(
  ChainId.ETHEREUM,
  '0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48',
)

const inferred = normalizeAddress(
  '0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48',
)
```

## Native addresses

`getNativeAddress` returns the native address representation for a chain.

```ts twoslash
import { ChainId, getNativeAddress } from 'sushi'

const native = getNativeAddress(ChainId.ETHEREUM)
```

## IDs

Sushi IDs use the `chainId:address` format. Native assets can optionally translate the native address to `NATIVE`.

```ts twoslash
import { ChainId, getChainIdAddressFromId, getIdFromChainIdAddress } from 'sushi'

const id = getIdFromChainIdAddress(
  ChainId.ETHEREUM,
  '0xa0b86991c6218b36c1d19d4a2e9eb0ce3606eb48',
)

const parsed = getChainIdAddressFromId(id)
```

## Wrapped native support

```ts twoslash
import { ChainId, isWNativeSupported } from 'sushi'

isWNativeSupported(ChainId.ETHEREUM)
```

`isWNativeSupported` currently supports EVM and SVM chain IDs.

## Slippage

`subtractSlippage` subtracts a decimal slippage value from an `Amount`.

```ts twoslash
import { Amount, subtractSlippage } from 'sushi'

declare const amount: Amount

const minimum = subtractSlippage(amount, 0.01)
```

The `slippage` argument must be between `0` and `1`, where `0.01` means `1%`.

## LowercaseMap

`LowercaseMap` lowercases keys for `get`, `has`, `set`, and `delete`.

```ts twoslash
import { LowercaseMap } from 'sushi'

const map = new LowercaseMap<string, number>()

map.set('ABC', 1)
map.get('abc') // 1
```

## assertNever

Use `assertNever` to enforce exhaustive checks.

```ts twoslash
import { assertNever } from 'sushi'

type State = 'idle' | 'loading'

function label(state: State) {
  switch (state) {
    case 'idle':
      return 'Idle'
    case 'loading':
      return 'Loading'
    default:
      return assertNever(state)
  }
}
```