# unicorn/prefer-logical-operator-over-ternary

> Require `||` or `??` instead of a ternary that repeats its condition

`user.name ? user.name : "Anonymous"` writes `user.name` twice and evaluates it twice. `user.name || "Anonymous"` gives the same result and evaluates it once.

The rule reports `a ? a : b` and `!a ? b : a`.

## Configure

Off by default. To turn it on:

```toml bunfig.toml
[lint.rules]
"unicorn/prefer-logical-operator-over-ternary" = "error" # or "warn"
```

## Examples

Reported:

```js
const name = user.name ? user.name : "Anonymous";
const port = !config.port ? 3000 : config.port;
```

Not reported:

```js
const name = user.name || "Anonymous";
const port = config.port || 3000;
```

If the fallback is only meant for `null` and `undefined`, so that `0` and `""` are kept, use `??`:

```js
const port = config.port ?? 3000;
```