What is the simplest way to get a substring in Ruby by removing a specific number of characters from the end?

General Discussions
1

What is the simplest way to get a substring in Ruby by removing a specific number of characters from the end?

I have the following string:

a_string = "a1wer4zx"

I want to remove the last 3 characters, resulting in "a1wer". Currently, my approach feels overly complicated:

an_array = a_string.split(//, (a_string.length - 2))  
an_array.pop  
new_string = an_array.join

What is a more efficient way to achieve this using Ruby substring operations?

2

If you just need to remove the last character, the easiest way is chop.

a_string = "a1wer4zx"
new_string = a_string.chop
# => "a1wer4z"

chop removes the last character, which is useful for things like trimming newline characters. But since you need to remove multiple characters, we need a different approach.

3

Using slice for Precise Character Removal : That’s good for one character, but for removing multiple characters, slice is more flexible.

a_string = "a1wer4zx"
new_string = a_string[0..-4]
# => "a1wer"

Here, 0…-4 tells Ruby to take everything except the last three characters. It’s a clean and readable way to get the substring.

4

Using chomp if Dealing with Known Suffixes :

Both of those are solid solutions, but if you know the exact suffix you want to remove, chomp can be useful too.

a_string = "a1wer4zx"
new_string = a_string.chomp("4zx")
# => "a1wer"

This works well when you’re dealing with known endings, like removing a file extension.