Interview Q&A / JavaScript
JavaScript interview questions
Closures, the event loop, this, promises and the core language questions every frontend round asks.
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- How does the this keyword work in JavaScript?
this is decided by how a function is called, not where it is written. A method call obj.fn() sets this to obj; new sets it to the new object; call, apply and bind set it explicitly; a plain call gives undefined in strict mode. Arrow functions have no own this and use the surrounding one.
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