3 ms·

There would at least be some ambiguity with single-value lists otherwise: If numbers: 1, 2, 3 was a list, what would numbers: 1 be?

• jampekka 1y ago
  You could have it like in Python tuples where 1 is a scalar and 1, is a tuple.
  • xg15 1y ago
    True, but I think that wouldn't be any more intuitive or error safe than the :: syntax.
    • renox 1y ago
      Error safe, the : or :: I kind of doubt it, I think that finding a typing mistake (two : instead of 1) won't be easy..