var array = [
{
    name:"bob",
    planet:"earth"
},
{
    name:"mike",
    planet:"mars"
},
{
    name:"vlad",
    planet:"jupiter"
}];

var filtered = array.filter(function(x){
    return x.name !== "mike";
});

console.log(array); //lets print how normal array looks like
console.log("---");
console.log(filtered); //lets print how filtered one looks like

for(var i = 0; i < filtered.length; i++)
{
    delete filtered[i].planet; //remove planet
    filtered[i].name = filtered[i].name + "[NEW]"; //add NEW to the name
}

console.log("After replacement:");
console.log(array);//lets print how normal array looks like now
console.log("-----------");
console.log(filtered);//lets print how filtered array looks like now

[ { name: 'bob', planet: 'earth' },
  { name: 'mike', planet: 'mars' },
  { name: 'vlad', planet: 'jupiter' } ] //this array is normal
---
[ { name: 'bob', planet: 'earth' },
  { name: 'vlad', planet: 'jupiter' } ] //this is good behavior, since I don't need "mike"

After replacement:

[ { name: 'bob[NEW]' },
  { name: 'mike', planet: 'mars' },
  { name: 'vlad[NEW]' } ] //this should not be changed in any way
-----------
[ { name: 'bob[NEW]' }, { name: 'vlad[NEW]' } ] //this is correct

for(var i = 0; i < filtered.length; i++)
{
    delete filtered[i].planet; //remove planet
    filtered[i].name = filtered[i].name + "[NEW]"; //add NEW to the name
}

var a = [{answer:null}];
var b = a.filter(function() { return true; }); // Just a copy, but using `filter` for emphasis
a[0].answer = 42;
console.log(b[0].answer); // 42

a[0].answer = 42;

var a = [{answer:null}];

a

var b = a.filter(function() { return true; }); // Just a copy, but using `filter` for emphasis

a[0].answer = 42;

a[0].answer = 42;

console.log(b[0].answer);

console.log(b[0].answer);

var filtered = [];
array.forEach(function(x){
    if (x.name !== "mike") {
        filtered.push({name: x.name + "[NEW]"});
    }
});