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Deep Dive into JavaScript Functions

Francisco Inoque on September 24, 2023

Deep Dive into JavaScript Functions Functions are a fundamental concept in JavaScript, allowing you to define reusable blocks of code th...
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Joshua Newell Diehl •

So fun! I love me some functional js.
Check out this neat constructor syntax!

const Counter = (count) => ({
    current: () => count,
    increment: () => count++,
    decrement: () => count--,
    adjust: (amount) => count += amount
})
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peerreynders •

Typically that's called a factory function as it isn't used with the new operator.

When a function is used as a constructor (i.e. is invoked with the new operator) it needs to work with a dynamically bound this which represents the object under construction.

Given that arrow function expressions have their this statically bound to the environment that created them only regular function declarations (and regular function expressions) can used as constructors.

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Joshua Newell Diehl •

Check out this neat factory function syntax

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Jon Randy 🎖️ • • Edited

Closures are inner functions that have access to the variables of their outer functions even after the outer function has completed its execution. This is useful for creating encapsulation.

Closures are NOT functions. They are the combination of a function bundled together with references to its surrounding state. ALL functions have an associated closure, not just ones created inside others.