Ruby inject with index and brackets

Question

I try to clean my Code. The first Version uses each_with_index. In the second version I tried to compact the code with the Enumerable.inject_with_index-constr

Answer 1

lines = %w(a b c)
indexes = lines.each_with_index.inject([]) do |acc, (el, ind)|
  acc << ind - 1 if el == "b"
  acc
end

indexes # => [0]