Elaboration:
In response to your request for a description, my aim is to simplify the explanation:
When you use the sort function on an array, it expects two elements to compare and returns a numeric value indicating their relationship ("less than" as negative, "greater than" as positive, or "equal" as zero). Therefore, the function will be invoked multiple times based on your scenario. It is also possible, in theory, not to have these two arguments; for instance, to achieve a random order, you could do:
cars.sort(() => Math.random() - 0.5)
Essentially, any function that yields a number can facilitate sorting arrays. In your context, it would entail:
Sorting based on defined categories hierarchy / utilizing IDs for identical categories:
const cars: { id: number; category: string }[] = [
{ id: 3, category: "fast car" },
{ id: 0, category: "fast car" },
{ id: 1, category: "slow car" },
{ id: 2, category: "fast car" }
];
const orderCategory = { 'fast car': 1, 'slow car': 2 };
cars.sort((carA, carB) => {
if (carA.category !== carB.category) {
return orderCategory[carA.category] - orderCategory[carB.category];
} else {
return carA.id - carB.id;
}
});
console.log(cars);
A couple of additional recommendations:
- You can utilize
const instead of let in this scenario
- No need for quotation marks around
id and category
I hope this explanation proves helpful! Keep coding with enthusiasm!
EDIT: Code formatting enhanced.
EDIT 2: I noticed your preference for fast cars being listed first. My earlier method achieved this due to alphabetical order correlation (F < S). If alphabetical order isn't the reason behind this priority, you must define categories accordingly. You could change "fast car" to "sports car" (uniformly) for desired listing precedence over "slow car" entries, despite alphabetic sequence suggesting otherwise.
I have now adjusted the preceding code. This was the former implementation emphasizing alphabetically sorted categories:
Alphabetical categorization / employing IDs for same-category resolution:
cars.sort((carA, carB) => {
if (carA.category < carB.category) {
return -1;
} else if (carA.category > carB.category) {
return 1;
}
// equivalently: else if (carA.category === carB.category)
else {
return carA.id - carB.id;
}
});
EDIT 3: Adjusted randomness example clarifications within the explanation. The Math.random() function outputs within a range of 0 to 1. Thus, subtracting 0.5 from it induces randomized negative values for variety.