---
type: "fhirpath-function"
title: "FHIRPath Function: all"
function: "all"
category: "Existence"
section: "5.1.3"
source: "fhirpath/functions.json"
---
# FHIRPath Function: all
> This is a [scoped function](#scoped-functions): The `criteria` argument is evaluated for each item (setting `$this` and `$index` before each iteration); if all return `true` then the function returns `true`, otherwise `false`. An empty input collection returns `true`.

Returns `true` if for every item in the input collection, `criteria` evaluates to `true`. Otherwise, the result is `false`. If the input collection is empty (`{ }`), the result is `true`.

``` fhirpath
generalPractitioner.all($this.resolve() is Practitioner)
```

This example returns `true` if all of the `generalPractitioner` elements are of type `Practitioner`.
## Summary
- **Category**: Existence
- **Section**: `5.1.3`
- **Return Type**: `Boolean`
- **Empty Input Result**: `true`
- **Errors on Multiple Input**: `false`
## Description
Returns `true` if for every element in the input collection, `criteria` evaluates to `true`. Otherwise, the result is `false`.
## Arguments
- `criteria`: `expression` - Expression to evaluate against each element
## Type Mapping
- `Any-Boolean`
## Example
```fhirpath
generalPractitioner.all($this.resolve() is Practitioner)
```