Object Spread - Supercharged

Surma shows you the new Object Spread operator “...” in JavaScript.

[LarsRyeJeppesen]

Very handy for Redux reducers because it is immutable... using it all the time, loving it immensely

[durchschnittlich]

I didn't think about it like that. Thanks!

[r-i-ch]

1. How does the object spread differ from Object.assign({}, obj1, obj2)
2. Does it do 'deep copying' or are the non-primitive values related back to their source object?
3. Is it like Obj.assign in that any duplicated properties will be overwritten by the right-most object?

[dandan]

this ellipsis "..." symbol before variables are present in other contexts too: funcion definitions, object creations and array creations; but people are starting to give them different names. i always thought of the "..." as the "spread operator"

function foo( ...args ) { /* "args" will be an array but the good old "arguments" is present too */ }

object2 = { ...object1, ...array1, other_variable, key: 'value' } // mixing arrays and objects (eew)

array2 = [...array3, 2, 3, 4] // cant mix objects here (phew)

[chris-eg]

does this work like Object.assign(a, b)?
is the newly created object "both", a new Object or will changing "a.a1"affect "both.a1"

[Jeremybelleu]

Would this be able to work with object destructuring? E.g. in the parameter instead of reassigning on the parameter on a new line

[talgatsaribayev]

Isn't it bad practice to reassign function arguments, especially if it is object?

[MrMcCoyD]

This isn’t supported yet in Edge or Safari