Ruby: how can I copy a variable without pointing to the same object?

Question

In Ruby, how can I copy a variable so that changes in the original do not affect the copy?

For example:

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

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

Answer 1

As for copying, you can do:

 phrase2 = phrase1.dup 

or

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

You can do this to avoid copying at all:

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

Answer 2

Using your example, instead of:

 phrase2 = phrase1 

Try:

 phrase2 = phrase1.dup 

Answer 3

 phrase1 = "Hello Jim" # => "Hello Jim" phrase2 = Marshal.load(Marshal.dump(phrase1)) # => "Hello Jim" phrase1.gsub!("Hello","Hi") # => "Hi Jim" puts phrase2 # "Hello Jim" puts phrase1 # "Hi Jim"