# Changing a value inside nested collections

[Syntax and values](README.md)

A list can contain maps, and a map can contain lists. Follow a path through these collections to change one value, like finding a card inside a box inside a cupboard.

In `players[0].stats.score`, the **root** is the starting name `players`. `[0]` selects the first list item; `.stats` and `.score` select named map entries. Those added parts are called **suffixes**. The root must be a name you may update, and every place or key along the path must already exist. `set` changes the final value; it does not create missing places.

Index and member suffixes can be combined when the root is assignable:

```pliro
# language: en
let players = [
    {"name": "Pip", "stats": {"score": 0, "lives": 3}},
]

set players[0].stats.score = 100
say players[0].name, players[0].stats.score
```

## Example

```pliro
# language: en
let players = [{"score": 12}]
set players[0].score = 20
say players[0].score
```

## Related entries

[Syntax and values](README.md) · [Built-ins](../builtins/README.md) · [Programming guides](../guides/README.md)