---
title: "JSValueCompare(_:_:_:_:)"
framework: JavaScriptCore
role: symbol
role_heading: Function
platforms: [iOS 18.0+, iPadOS 18.0+, Mac Catalyst 18.0+, macOS 15.0+, tvOS 9.0+, visionOS 2.0+]
path: "javascriptcore/jsvaluecompare(_:_:_:_:)"
---

# JSValueCompare(_:_:_:_:)

## Declaration

```swift
func JSValueCompare(_ ctx: JSContextRef, _ left: JSValueRef, _ right: JSValueRef, _ exception: UnsafeMutablePointer<JSValueRef?>?) -> JSRelationCondition
```

## Parameters

- `ctx`: The execution context to use.
- `left`: The JSValue as the left operand.
- `right`: The JSValue as the right operand.
- `exception`: A pointer to a JSValueRef in which to store an exception, if any. To reliable detect exception, initialize this to null before the call. Pass NULL if you do not care to store an exception.

## Return Value

Return Value A value of JSRelationCondition, a kJSRelationConditionUndefined is returned if an exception is thrown.

## Discussion

Discussion Compares two JSValues. The result is computed by comparing the results of JavaScript’s ==, <, and > operators. If either left or right is (or would coerce to) NaN in JavaScript, then the result is kJSRelationConditionUndefined.