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What is the return value of the following Ruby code?
words = [["abc", ["def"]], "ghi"] words[0][0][0][1] # => ???
The correct answer is
["def"]
"b"
"ghi"
nil
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Let's detail what happens step-by-step
words = [["abc", ["def"]], "ghi"] words[0][0][0][1]
is equivalent to
words = [["abc", ["def"]], "ghi"] words[0] # => ["abc", ["def"]] words[0][0] # => "abc" words[0][0][0] # => "a" words[0][0][0][1] # => nil
In the original code, words[0][0][0][1] attempts to access the second character of the single-character string "a" using nested indexing.
However, since "a" is a single-character string, trying to access the second character results in nil being returned by String#[].
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