JS array remove side by side duplicate strings

Question

I have array, for example:

var arr = ['ab', 'cd', 'cd', 'ef', 'cd'];

Now I want to remove duplicates which is side by side, in this example it's at index 1 & 2 (cd).

result must be:

var arr = ['ab', 'cd', 'ef', 'cd'];

I tried this code but it's not working:

var uniqueNames = [];
$.each(arr, function(i, el){
    if($.inArray(el, uniqueNames) === -1) uniqueNames.push(el);
});

but this filters unique and I don't want this.

Answer 1

You could check the successor and filter the array.

var array = ['ab', 'cd', 'cd', 'ef', 'cd'],
    result = array.filter((a, i, aa) => a !== aa[i + 1]);
    
console.log(result);

Answer 2

One way of doing this

var arr = ['ab', 'cd', 'cd', 'ef', 'cd'];
var uniqueNames = [];
$.each(arr, function(i, el){
    if(el != uniqueNames[i-1]) uniqueNames.push(el);
});
console.log(uniqueNames);

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