# .every(callback)

## Description

The `every` method tests whether all elements in the array pass the test implemented by the provided callback function. It returns a Boolean value.

## Parameters

The `every` method requires the array to test and the custom function that defines the test for each element.

## Usage On Arrays

In the provided examples, the `every` method is used to check if all elements in the array `num`, which contains the numbers `[1,2,3,4,5]`, are greater than 0.

* A separate function `isPositive` is defined using the syntax `def isPositive(item)`.
* Inside the function, `item > 0` is returned, which checks if each item is greater than 0.
* `num.every(isPositive)` is called, applying the `isPositive` function to each element, resulting in `true` since all elements are greater than 0.

{% code overflow="wrap" %}

```javascript
num = [1,2,3,4,5]

def isPositive(item) (
  return item > 0
)

log num.every(isPositive)
// true
```

{% endcode %}

## More Examples

The following example demonstrates how to use the `every` method with an inline function.

{% code overflow="wrap" %}

```javascript
num = [1,2,3,4,5]

log num.every(def(item) -> (
  return item > 0
))
// true
```

{% endcode %}

## Lambdas

The `every` method can also be used with lambda functions.

{% code overflow="wrap" %}

```javascript
num = [1,2,3,4,5]

log num.every(item -> item > 0)
// true
```

{% endcode %}