Replace in array using lodash

Question

Is there an easy way to replace all appearances of an primitive in an array with another one. So that ['a', 'b', 'a', 'c'] would become ['x', 'b', 'x', 'c'] when replacing a with x. I'm aware that this can be done with a map function, but I wonder if have overlooked a simpler way.

Answer 1

In the specific case of strings your example has, you can do it natively with:

myArr.join(",").replace(/a/g,"x").split(",");

Where "," is some string that doesn't appear in the array.

That said, I don't see the issue with a _.map - it sounds like the better approach since this is in fact what you're doing. You're mapping the array to itself with the value replaced.

_.map(myArr,function(el){
     return (el==='a') ? 'x' : el;
})

Answer 2

I don't know about "simpler", but you can make it reusable

function swap(ref, replacement, input) {
    return (ref === input) ? replacement : input;
}

var a = ['a', 'b', 'a', 'c'];

_.map(a, _.partial(swap, 'a', 'x'));