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# JavaScriptCore

Evaluate JavaScript programs from within an app, and support JavaScript scripting of your app.

## Overview

The JavaScriptCore framework provides the ability to evaluate JavaScript programs from within Swift, Objective-C, and C-based apps. You can use also use JavaScriptCore to insert custom objects into the JavaScript environment.

## Topics

### Execution Environment

[`class JSVirtualMachine`](/documentation/JavaScriptCore/JSVirtualMachine)

A self-contained environment for JavaScript execution.

[`class JSContext`](/documentation/JavaScriptCore/JSContext)

A JavaScript execution environment.

### JavaScript Code

[`class JSValue`](/documentation/JavaScriptCore/JSValue)

A JavaScript value.

[`class JSManagedValue`](/documentation/JavaScriptCore/JSManagedValue)

A JavaScript value with conditional retain behavior to provide automatic memory management.

### Native Code

[`protocol JSExport`](/documentation/JavaScriptCore/JSExport)

The protocol for exporting Objective-C objects to JavaScript.

### C API

[C JavaScriptCore API](/documentation/JavaScriptCore/c-javascriptcore-api)

Browse the alternative C-based APIs for JavaScriptCore.

### Reference

[JavaScriptCore Constants](/documentation/JavaScriptCore/javascriptcore-constants)

### Variables

[`var kJSTypeBigInt: JSType`](/documentation/JavaScriptCore/kJSTypeBigInt)

### Functions

[`func JSBigIntCreateWithDouble(JSContextRef, Double, UnsafeMutablePointer<JSValueRef?>?) -> JSValueRef`](/documentation/JavaScriptCore/JSBigIntCreateWithDouble(_:_:_:))

[`func JSBigIntCreateWithInt64(JSContextRef, Int64, UnsafeMutablePointer<JSValueRef?>?) -> JSValueRef`](/documentation/JavaScriptCore/JSBigIntCreateWithInt64(_:_:_:))

[`func JSBigIntCreateWithString(JSContextRef, JSStringRef, UnsafeMutablePointer<JSValueRef?>?) -> JSValueRef`](/documentation/JavaScriptCore/JSBigIntCreateWithString(_:_:_:))

[`func JSBigIntCreateWithUInt64(JSContextRef, UInt64, UnsafeMutablePointer<JSValueRef?>?) -> JSValueRef`](/documentation/JavaScriptCore/JSBigIntCreateWithUInt64(_:_:_:))

[`func JSValueCompare(JSContextRef, JSValueRef, JSValueRef, UnsafeMutablePointer<JSValueRef?>?) -> JSRelationCondition`](/documentation/JavaScriptCore/JSValueCompare(_:_:_:_:))

[`func JSValueCompareDouble(JSContextRef, JSValueRef, Double, UnsafeMutablePointer<JSValueRef?>?) -> JSRelationCondition`](/documentation/JavaScriptCore/JSValueCompareDouble(_:_:_:_:))

[`func JSValueCompareInt64(JSContextRef, JSValueRef, Int64, UnsafeMutablePointer<JSValueRef?>?) -> JSRelationCondition`](/documentation/JavaScriptCore/JSValueCompareInt64(_:_:_:_:))

[`func JSValueCompareUInt64(JSContextRef, JSValueRef, UInt64, UnsafeMutablePointer<JSValueRef?>?) -> JSRelationCondition`](/documentation/JavaScriptCore/JSValueCompareUInt64(_:_:_:_:))

[`func JSValueIsBigInt(JSContextRef, JSValueRef) -> Bool`](/documentation/JavaScriptCore/JSValueIsBigInt(_:_:))

[`func JSValueToInt32(JSContextRef, JSValueRef, UnsafeMutablePointer<JSValueRef?>?) -> Int32`](/documentation/JavaScriptCore/JSValueToInt32(_:_:_:))

[`func JSValueToInt64(JSContextRef, JSValueRef, UnsafeMutablePointer<JSValueRef?>?) -> Int64`](/documentation/JavaScriptCore/JSValueToInt64(_:_:_:))

[`func JSValueToUInt32(JSContextRef, JSValueRef, UnsafeMutablePointer<JSValueRef?>?) -> UInt32`](/documentation/JavaScriptCore/JSValueToUInt32(_:_:_:))

[`func JSValueToUInt64(JSContextRef, JSValueRef, UnsafeMutablePointer<JSValueRef?>?) -> UInt64`](/documentation/JavaScriptCore/JSValueToUInt64(_:_:_:))

### Enumerations

[`enum JSRelationCondition`](/documentation/JavaScriptCore/JSRelationCondition)

---

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