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Closure Simulator

Lexical Environment ยท Scope Chain ยท Memory Lifecycle
Code Editor
Example:
Speed:500ms/step
idle
Console
Console output will appear here.

Key Concepts

env

Lexical Environment

Lexical Environment โ€” Each function creates an environment object that holds its local variables.

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[[Outer]] Reference

Outer Reference โ€” Every environment has a [[Outer]] pointer to its parent, forming the scope chain.

GC

Memory Lifecycle

Memory Lifecycle โ€” When a function returns, its environment stays in memory if a closure references it (retained). When no closures reference it, it becomes eligible for garbage collection.

On StackRetainedGC'd

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