Remove Object Properties with Destructing

removeItem.js

// Helper method to delete without mutating
// Why not use delete? It's a mutable operation (side-effects).
// By using object destructuring, we have a one-liner approach.
// Inspired by: https://ultimatecourses.com/blog/remove-object-properties-destructuring
const removeItem = (key, { [key]: _, ...obj }) => obj;


// How does this work?
// We pass in the name of the key we wish to remove from the object.
// For the second param, we pass in the object
// However the method itself, destructures the object by
// taking the key and by wrapping it in brackets it
// dynamically creates a new variable and assings it "blank"
// If we wanted to reference the deleted value we could provide
// a name instead of "_". 
// However for our purpose we don't wish to refer back so we pass blank.
// the fn then just returns the obj. However, the object now excludes 
// the key in question because the rest protocol gives us everything 
// left over via destructring.

// Example
/*
 const foo = {
   herp: 'Herp',
   derp: 'Derp',
 }
    
 const boo = removeItem('herp', foo);
 console.log('Boo:');
 console.log(boo);
 console.log('Foo:');
 console.log(foo);
 
 // output
 // Boo:
 // { derp: "Derp" }
 // Foo:
 // { herp: "Herp", derp: "Derp" }