Ruby:如何在不指向同一个对象的情况下复制变量? [英] Ruby: how can I copy a variable without pointing to the same object?

问题描述

在 Ruby 中，如何复制一个变量以使对原始变量的更改不影响副本?

In Ruby, how can I copy a variable such that changes to the original don't affect the copy?

例如:

phrase1 = "Hello Jim"
phrase2 = phrase1
phrase1.gsub!("Hello","Hi")
p phrase2 #outputs "Hi Jim" - I want it to remain "Hello Jim"

在这个例子中，两个变量指向同一个对象；我想为第二个变量创建一个新对象，但它最初包含相同的信息.

In this example, the two variables point to the same object; I want to create a new object for the second variable but have it contain the same information initially.

推荐答案

至于复制你可以这样做:

As for copying you can do:

phrase2 = phrase1.dup

或

# Clone: copies singleton methods as well
phrase2 = phrase1.clone

您也可以这样做以避免完全复制:

You can do this as well to avoid copying at all:

phrase2 = phrase1.gsub("Hello","Hi")

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