Interface: Pass two array of specific length as prop

I have an interface like this

interface FooProps {
    cat: string[],
    kitten: number[],

Is there any way to tell TypeScript that kitten and cat must be the same length? Note, the length varies, depending on where the interface FooProps is used. But, whenever I use FooPros, the length of cat and kitten must be the same.

>Solution :

interface FooProps {
  cat: string[];
  kitten: number[];

// If cat and kitten are of fixed same length then
// the easiest way would be to define them as supple

interface FooPropsAsTupple {
  cat: [string, string];
  kitten: [number, number];

const catsTupples: FooPropsAsTupple = {
  cat: ["", ""],
  kitten: [1, 2],

// however if they are dynamic, then you need to validate
// using a class (There are other ways too but this is easy)

class Felines implements FooProps {
  constructor(props: FooProps) {
    if ( !== props.kitten.length) {
      throw new Error(`Cat and kitten must have the same length`);
    const { cat, kitten } = props; = cat;
    this.kitten = kitten;
  public cat!: string[];
  public kitten!: number[];

// Error: Cat and kitten must have the same length
new Felines({ cat: ["", "", ""], kitten: [1, 2] });

You may even combine both approach in order to get type completion but also actual safety by throwing error.

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