function isSingleBlockStatement(node) {
            return node && node.type === 'BlockStatement' &&
            node.body.length === 1;
        }
Disallows curly braces after statements.

Types: `Array` or `Boolean`

Values: Array of quoted keywords or `true` to disallow curly braces after the following keywords:

#### Example

```js
"disallowCurlyBraces": [
    "if",
    "else",
    "while",
    "for",
    "do",
    "with"
]
```

##### Valid

```js
if (x) x++;
```

##### Invalid

```js
if (x) {
    x++;
}
```