Ruby Q & A


What are comments in Ruby, and how to use them?

In Ruby, comments are essential for documenting your code and making it more understandable for both yourself and other developers who may work with your code in the future. Comments are text annotations within your code that are not executed as part of the program. They serve as explanatory notes or reminders about the code’s purpose and functionality. Ruby supports two main types of comments:

  1. Single-line Comments: Single-line comments are preceded by a `#` (hash) symbol and are used for adding comments on a single line. Anything following the `#` symbol on that line is treated as a comment and is ignored by the Ruby interpreter. Single-line comments are typically used for brief explanations or clarifications within the code.

   # This is a single-line comment

   x = 10  # Another comment, this time on the same line as code



  1. Multi-line Comments: Ruby does not have a built-in syntax for multi-line comments like some other languages. However, developers often use documentation strings (also known as docstrings) enclosed in `=begin` and `=end` to create multi-line comments. While this is not a true comment feature, it serves the same purpose and is commonly used for longer explanations and comments.


   This is a multi-line comment.

   It can span across multiple lines.




   Note that it’s more common in Ruby to use documentation strings for documenting methods and classes, where tools like RDoc and YARD can generate documentation from these comments.

Comments are crucial for maintaining code readability, providing context, and explaining complex or non-obvious code sections. It’s considered good practice to include meaningful comments in your Ruby code to make it easier to understand and maintain, especially for larger and more complex projects.

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Experienced software professional with a strong focus on Ruby. Over 10 years in software development, including B2B SaaS platforms and geolocation-based apps.