For loops nested inside each other

Question

I'm trying to write a script that will return me all possible combinations for some parameters. Here is what I currently have. The problem is that length of tagsLoop list can change and then I would need another for loop inside the most nested loop. And then another one and another one. I'm adding screenshot with variables that I use to loop over.

Edit: added working snippet

 var tagsLoop = ["mobile_size", "desktop_size", "tag_test"]
 var bigArray = [{tag: "mobile_size", key: "size", val: "6"},
 {tag: "mobile_size", key: "size", val: "2"},
 {tag: "desktop_size", key: "size", val: "10"},
 {tag: "desktop_size", key: "size", val: "20"},
 {tag: "tag_test", key: "oracle", val: ""},
 {tag: "tag_test", key: "pros", val: ""}]
 for (var i = 0; i < bigArray.length; i++) {
 if (bigArray[i]['tag'] == tagsLoop[0]) {
 var part1 = bigArray[i]['key'] + '=' + bigArray[i]['val']
 for (var j = 0; j < bigArray.length; j++) {
 if (bigArray[j]['tag'] == tagsLoop[1]) {
 var part2 = "&" + bigArray[j]['key'] + '=' + bigArray[j]['val']
 for (var k = 0; k < bigArray.length; k++) {
 if (bigArray[k]['tag'] == tagsLoop[2]) {
 var part3 = "&" + bigArray[k]['key'] + '=' + bigArray[k]['val']
 console.log(part1, part2, part3)
 }
 }
 }
 }
 }
 }

enter image description here

• Carcigenicate: If you need an arbitrary depth, that usually suggests that you need recursion. If you google "variable number of nested for loops", your should be able to find examples.
• Federico klez Culloca: Why should tagLoop change during your iterations? And what does it mean?
• AlienDeg: @FedericoklezCulloca it doesn't change during the iteration, but it depends on user output. so it may change over time. Sorry for not making it clear.
• AlienDeg: @asynts yep, sorry for that. forgot about variables. added now.

Answer 1

You could get the grouped data first and the build new arrays with the combinations of the wanted items and their values.

function getCartesian(array, keys) {
 var temp = array.reduce((r, { tag, key, val }) => {
 (r[tag] = r[tag] || []).push([key, val].join('='));
 return r;
 }, Object.create(null));
 return keys
 .map(k => temp[k])
 .reduce((a, b) => a.reduce((r, v) => r.concat(b.map(w => [].concat(v, w))), []))
 .map(a => a.join('&'));
}
var array = [{ tag: "mobile_size", key: "size", val: "6" }, { tag: "mobile_size", key: "size", val: "2" }, { tag: "desktop_size", key: "size", val: "10" }, { tag: "desktop_size", key: "size", val: "20" }, { tag: "tag_test", key: "oracle", val: "" }, { tag: "tag_test", key: "pros", val: "" }],
 tags = ["mobile_size", "desktop_size", "tag_test"],
 result = getCartesian(array, tags);
console.log(result);

.as-console-wrapper { max-height: 100% !important; top: 0; }