Question

So, title says most of it, and I’ll give an example:

var foo = ['one', 'two', 'three'];
var bar = [
        {   
            integer: 1,
            string: 'one'
        },
        {   
            integer: 3,
            string: 'three'
        }       
    ];

Now, I’m wondering how can I get the list of positive matches for each of the elements in foo against each of the string properties of all the objects in array bar.

Answer 1

First, make a set of all elements in foo to avoid square complexity:

var fooSet = {};    
for(var i = 0; i < foo.length; i++) {
    var e = foo[i];
    fooSet[e] = true;
}

Then, go through bar and gather matches:

var matches = [];
for(var i = 0; i < bar.length; i++) {
    var e = bar[i];
    if(fooSet[e.string]) {
           matches.push(e);
    }
}

After this, matches array will contain the elements from bar that match the elements of foo.

Here’s a live example:

• http://jsfiddle.net/mfAc4/