---
title: Stack.attr()
---
The `Stack.attr()` method adds an attribute to the stack
and returns the original stack.
Setting the third parameter to `true` will replace the value of the
attribute instead of adding it.
## Stack.attr() signature
```js
Stack stack.attr(
string name,
mixed value,
bool overwrite = false
```
If the third parameter is set to `true` it will call
`this.attributes.set()` instead,
thereby overwriting the value of the attribute.
:::noteThis method is chainable as it returns the Stack object:::
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