What is the easiest way to replace a word in a string in Ruby?

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1

What is the easiest way to replace a word in a string in Ruby?

I have the following string:

sentence = "My name is Robert"

How can I replace a specific word in this sentence without using complex code or a loop? What are the best methods for Ruby string replace operations?

2

The simplest way to replace a word in Ruby is to use sub. It replaces the first occurrence of a match.

sentence = "My name is Robert"
sentence.sub("Robert", "John")
# => "My name is John"

This works well when you only need to replace the first occurrence and don’t need to modify the original string.

3

That’s great if you only need to replace one instance, but if you’re dealing with multiple occurrences of the same word, gsub is better since it replaces all occurrences.

sentence = "Robert is my friend. Robert is nice."
sentence.gsub("Robert", "John")
# => "John is my friend. John is nice."

So if you have a long text and need to replace multiple words, gsub is the way to go.

4

Those are solid options, but what if the word appears in different cases? You can use gsub with a regex to perform a case-insensitive replacement.

sentence = "My name is robert and ROBERT is my friend."
sentence.gsub(/robert/i, "John")
# => "My name is John and John is my friend."

This makes sure all variations of ‘robert’ get replaced, regardless of capitalization.