---
type: "fhirpath-operator"
title: "FHIRPath Operator: xor (xor)"
operator: "xor"
category: "Boolean Logic"
section: "6.5.4"
source: "fhirpath/operations.json"
---
# FHIRPath Operator: xor (xor)
Returns `true` if exactly one of the operands evaluates to `true`, `false` if either both operands evaluate to `true` or both operands evaluate to `false`, and the empty collection (`{ }`) otherwise:

|xor |true |false |empty |
| - | - | - | - |
|**true** |`false` |`true` |empty (`{ }`) |
|**false** |`true` |`false` |empty (`{ }`) |
|**empty** |empty (`{ }`) |empty (`{ }`) |empty (`{ }`) |
{:.grid}
## Summary
- **Category**: Boolean Logic
- **Section**: `6.5.4`
- **Left Argument**: `Boolean`
- **Right Argument**: `Boolean`
- **Return Type**: `Boolean`
- **Empty Input Result**: `empty`
- **Errors on Multiple Input**: `false`
## Description
Returns `true` if exactly one of the operands evaluates to `true`, `false` if either both operands evaluate to `true` or both operands evaluate to `false`, and empty collection otherwise.
## Type Mapping
- `Boolean-Boolean`