Should you rely on hoisting in production JavaScript code?
No. Relying on hoisting makes code harder to read and prone to bugs. Declare functions and variables at the top of their scope, and prefer const function expressions for predictable behavior.
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More FAQs in Function Hoisting vs Variable Hoisting in JavaScript
Function declarations are hoisted with their full body, so they can be called before the declaration line. var variables are hoisted with undefined, so referencing them early returns undefined and calling them as functions throws a TypeError.
No, not as functions. A function expression assigned to a var variable is hoisted as undefined. A function expression assigned to let or const sits in the TDZ. Either way, calling it before the line throws an error.
The function declaration wins because it is hoisted with its full body while var is hoisted with undefined. If there are multiple function declarations with the same name, the last one wins.
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