How do you approach hoisting questions in an interview?
Walk through the memory phase first: what is hoisted and to what value (undefined for var, full body for function declarations, TDZ for let/const). Then walk the execution phase line-by-line to determine each output.
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More FAQs in Common Hoisting Interview Questions in JavaScript
undefined. The var declaration is hoisted and initialized to undefined. The assignment a = 5 runs only when the line is reached, so the earlier log sees undefined.
TypeError: x is not a function. The var variable is hoisted with undefined, so calling it as a function fails. Only function declarations are hoisted with their body.
No. typeof on a let or const variable in the TDZ throws ReferenceError. typeof on a var that has not been assigned returns the string 'undefined' without throwing.
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