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## Recommended snippets

JavaScript's negation operator (`!`

) is a unary operator, used to invert the truth value of its operand. When used twice, known as the double negation operator (`!!`

), it can be used to convert a value to a boolean.

```
const x = 1;
const y = null;
!!x; // true
!!y; // false
```

Using the double negation operator is functionally equivalent to using the `Boolean()`

function, which we explored in depth in a previous article. In terms of readability and usability, I would still suggest using the `Boolean()`

function. It conveys the intent of the operation more clearly, and it's easier to understand at a glance.

```
const x = 1;
const y = null;
Boolean(x); // true
Boolean(y); // false
const values = [0, 0, 2, 0, 3];
// Kinda readable, but not great
values.filter(x => !!x); // [2, 3]
// Arguably more readable
values.filter(Boolean); // [2, 3]
```

### Check property

JavaScript, Function

Creates a function that will invoke a predicate function for the specified property on a given object.

### Negate predicate

JavaScript, Function

Negates a predicate function.

### Pipe async functions

JavaScript, Function

Performs left-to-right function composition for asynchronous functions.