4 ms·

FWIW, I fully support the notation `arr[-0]` as a solution to this problem.

• MauranKilom 6y ago
  So then what should this code produce? i = -0 return arr[i]
  • ufo 6y ago
    Actually, I think that might work in Javascript! All the numbers are IEE754 floating point numbers and there are separate values for positive and negative zero.
    • disk0 6y ago
      iirc using numeric literal values there's a coercion step—a console example: let arr = new Array(10); // 1e1 => 10 arr[1e1] = 1; console.log(`arr[10] === 1 => ${arr[10] === 1}`) console.log(`arr[1e1] === 1 => ${arr[1e1] === 1}`) So -0 becomes 0: arr[0] = 2; console.log(`arr[0] === 2 => ${arr[0] === 2}`); console.log(`arr[-0] === 2 => ${arr[-0] === 2}`); arr[-0] = 3; console.log(`arr[0] === 3 => ${arr[0] === 3}`); console.log(`arr[-0] === 3 => ${arr[-0] === 3}`);
  • thaumasiotes 6y ago
    So then what should this code produce? i = -0 return arr[i] That code would (assuming an integer value; the question is interesting without reference to the implementation of JavaScript) return arr[0], the first element. Don't think of arr[-1] as indexing the array with a negative number that might have been a positive number. Think of array access from the front, arr[ ], and array access from the back, arr[- ], as separate operations with separate syntax, each of which can accept only nonnegative numbers. arr[i] is of the first type, so you get the first element counted from the front.
• ufo 6y ago
  Even better: just make all arrays one-based instead of zero-based ;)