Question

How to create a range of numbers in TypeScript

Answer 1

const n: number = 10;
  
let rng: number[] = [...Array(n).keys()];
  
console.log(rng);
  
  
  
/*
run:
     
[0, 1, 2, 3, 4, 5, 6, 7, 8, 9] 
     
*/

 

70+ SQL courses for beginners and professionals

Answer 2

function range(start: number, end: number) : number[] {
    if (start === end) return [start];
      
    if (start > end) {
        throw Error(`"Error: start (${start}) >= end (${end})"`);
    }
      
    return [start, ...range(start + 1, end)];
}
  
let rng: number[] = range(2, 8);
  
console.log(rng);
  
  
  
/*
run:
     
[2, 3, 4, 5, 6, 7, 8]
     
*/

 

70+ SQL courses for beginners and professionals