I have an array of arrays and want to append elements to the sub-arrays. += does what I want, but I'd like to understand why push does not.
Behavior I expect (and works with +=):
b = Array.new(3,[])
b[0] += ["apple"]
b[1] += ["orange"]
b[2] += ["frog"]
b => [["apple"], ["orange"], ["frog"]]
With push I get the pushed element appended to EACH sub-array (why?):
a = Array.new(3,[])
a[0].push("apple")
a[1].push("orange")
a[2].push("frog")
a => [["apple", "orange", "frog"], ["apple", "orange", "frog"], ["apple", "orange", "frog"]]
Any help on this much appreciated.