# => ╰───┴───╯
```

## Iterating over Lists

To iterate over the items in a list, use the [`each`](/commands/docs/each.md) command with a [block](types_of_data.html#blocks)
of Nu code that specifies what to do to each item. The block parameter (e.g. `|elt|` in `{ |elt| print $elt }`) is the current list
item, but the [`enumerate`](/commands/docs/enumerate.md) filter can be used to provide `index` and `item` values if needed. For example:

```nu
let names = [Mark Tami Amanda Jeremy]
$names | each { |elt| $"Hello, ($elt)!" }
# Outputs "Hello, Mark!" and three more similar lines.

$names | enumerate | each { |elt| $"($elt.index + 1) - ($elt.item)" }
# Outputs "1 - Mark", "2 - Tami", etc.
```

The [`where`](/commands/docs/where.md) command can be used to create a subset of a list, effectively filtering the list based on a condition.

The following example gets all the colors whose names end in "e".

```nu
let colors = [red orange yellow green blue purple]
$colors | where ($it | str ends-with 'e')
# The block passed to `where` must evaluate to a boolean.
# This outputs the list [orange blue purple].
```

In this example, we keep only values higher than `7`.

```nu
let scores = [7 10 8 6 7]
$scores | where $it > 7 # [10 8]
```

The [`reduce`](/commands/docs/reduce.md) command computes a single value from a list.
It uses a block which takes 2 parameters: the current item (conventionally named `elt`) and an accumulator
(conventionally named `acc`). To specify an initial value for the accumulator, use the `--fold` (`-f`) flag.
To change `elt` to have `index` and `item` values, use the [`enumerate`](/commands/docs/enumerate.md) filter.
For example:

```nu
let scores = [3 8 4]
$"total = ($scores | reduce { |elt, acc| $acc + $elt })" # total = 15

$"total = ($scores | math sum)" # easier approach, same result

$"product = ($scores | reduce --fold 1 { |elt, acc| $acc * $elt })" # product = 96

$scores | enumerate | reduce --fold 0 { |elt, acc| $acc + $elt.index * $elt.item } # 0*3 + 1*8 + 2*4 = 16
```

## Accessing the List

::: tip Note
The following is a basic overview. For a more in-depth discussion of this topic, see the chapter, [Navigating and Accessing Structured Data](/book/navigating_structured_data.md).
:::

To access a list item at a given index, use the `$name.index` form where `$name` is a variable that holds a list.

For example, the second element in the list below can be accessed with `$names.1`.

```nu
let names = [Mark Tami Amanda Jeremy]
$names.1 # gives Tami
```

If the index is in some variable `$index` we can use the `get` command to extract the item from the list.