Do V8 and WebKit JavaScriptCore Implement String Interning?

String Interning in Common JavaScript Implementations: V8 and WebKit JavaScriptCore

JavaScript engines play a crucial role in executing JavaScript code effectively. Two widely used engines are V8 (employed by Google Chrome) and WebKit JavaScriptCore (employed by Safari and other browsers). When working with JavaScript strings, one key question arises: Do these engines utilize string interning?

String interning, in the context of programming languages, involves maintaining a single instance of identical strings in memory. This technique optimizes memory usage and performance by eliminating duplicate string instances.

Answer:

Yes, common JavaScript engines such as V8 and WebKit JavaScriptCore indeed employ string interning. Specifically, any literal string encountered in the JavaScript source, as well asidentifiers and other constant strings, are generally interned.

However, it's crucial to note that implementation details can vary. For instance, the exact criteria for what strings are interned may differ between different engines. Additionally, the timing of the interning process may also vary. Nonetheless, the general principle of interning identical strings remains consistent across common JavaScript engines.

It's worth pointing out that string interning only applies to primitive string values and not to String objects. String objects are distinct entities in JavaScript, and interning them would be incorrect behavior as it would hinder their unique object identities.

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