ruby on rails - Generate array of all combinations of an existing array -


if have array in ruby, this:

["foo", "bar", "bat"]

how can generate new array every combination of values?

i need output this:

["foo", "bar", "bat", "foo-bar", "foo-bat", "bar-bat", "foo-bar-bat"]

order unimportant. also, not need both "foo-bar" , "bar-foo".

the original array may have 5-6 members.

ar = ["foo", "bar", "bat"] p 1.upto(ar.size).flat_map {|n| ar.combination(n).map{|el| el.join('-')}} #=>["foo", "bar", "bat", "foo-bar", "foo-bat", "bar-bat", "foo-bar-bat"]

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