你可以使用to_s。
http://briancarper.net/2006/09/26/ruby-to_s-vs-to_str/

FWIW，inspect可能更像__repr__()而不是__str__()
从图书馆的参考资料中

repr（self）

Called by the repr() built-in function and by string conversions (reverse quotes) to compute the ``official'' string representation of an object. If at all possible, this should look like a valid Python expression that could be used to recreate an object with the same value (given an appropriate environment). If this is not possible, a string of the form "<...some useful description...>" should be returned. The return value must be a string object. If a class defines __repr__() but not __str__(), then __repr__() is also used when an ``informal'' string representation of instances of that class is required.个

在核心类上，它通常是“检查”。
例如：

irb(main):001:0> puts "array is: #{[1,2,3].inspect}"
array is: [1, 2, 3]
=> nil
irb(main):002:0> puts "array is: #{[1,2,3]}"
array is: 123
=> nil
irb(main):003:0>

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