Scope, Variable Lifetime & Closures

Understand block scope, lexical scope, variable lifetime in memory, and how closures encapsulate state.

Global Scope vs. Local Block Scope

Scope defines the visibility and lifetime of a variable:

Global Scope: Declared outside all functions; accessible from anywhere, but dangerous due to accidental overwrites.

Local / Block Scope: Declared inside a function or {} block; only visible inside that block and destroyed when the block finishes execution.

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+15 XP

Can code outside of a function access variables declared locally inside that function?