ルビーの穴

puts true and false #     (puts true) and false
puts (true and false) #
puts false and true #     (puts false) and true
puts (false and true) #     puts (false and true)
puts  true && false #     puts (true && false)
puts true & false #     puts (true & false)

結果
true
false
false
false
false
false
&&の優先度が&&より高い
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