if†x >= y y以上 x <= y y以下 パターン1†a = 10 if a > 10 then puts "BIG" else puts "Not big" end パターン2(省略系)†a = 10 puts "BIG" if a > 9 パターン3 (省略系)†a = 10 puts a > 9 ? "big" : "small" case†signal = "pink" case signal when "red" puts "STOP" when "yellow" puts "STOP" when "green", "blue" puts "GO" else puts "no signal" end |