Well if you wrote the array, or your program did, then you do know the length. Not a problem. Would it be nice if an array internally stored that? Sure. Does it

Well if you wrote the array, or your program did, then you do know the length. Not a problem. Would it be nice if an array internally stored that? Sure. Does it? No. Is that a real problem? No, not really - its been solved and worked around for decades