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具名元組

具名元組通常使用具名元組常值建立

tuple = {name: "Crystal", year: 2011} # NamedTuple(name: String, year: Int32)
tuple[:name]                          # => "Crystal" (String)
tuple[:year]                          # => 2011      (Int32)

要表示具名元組型別,您可以寫

# The type denoting a named tuple of x: Int32, y: String
NamedTuple(x: Int32, y: String)

在型別限制、泛型型別參數和其他需要型別的地方,您可以使用較短的語法,如型別語法中所述

# An array of named tuples of x: Int32, y: String
Array({x: Int32, y: String})

具名元組的鍵也可以是字串常值

{"this is a key": 1}