> For the complete documentation index, see [llms.txt](https://docs.atfinity.io/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.atfinity.io/rule-language/operators/string-operators/format.md).

# format

### Description

`format` takes a string and replaces all placeholders with values provided for them.

### Example: Formatting a Person Name

```
p is Person
"{name} {surname}".format(name: p.first_name, surname: p.last_name)
```

It is common practice to have two separate[ information fields](/guides/glossary/information.md) for a name - one for the first and one for the last name. If, once these data are collected, you want to treat the full name as one combined piece of information, you could use `format` like in the example above which returns a name like "Bruce Wayne".

### Example: For an E-Mail

The format operator is also very useful if you want to insert collected information into a larger string, e.g. an email. Let's say you would like to inform a client called "Clark Kent" about three new messages, then you could use the format operator like this:

```
p is Person
"Dear {name} {surname}

You have {new_messages} new messages."
.format(
    name: p.first_name,
    surname: p.last_name,
    new_messages: p.nr_of_new_messages
)
```

This would return the following message:

> Dear Clark Kent\
> You have 3 new messages.


---

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