Скачать или смотреть How to Effectively Escape and Print Forward Slash in Makefile's Goal Names Using Regular Expressions

Discover how to properly escape forward slashes in Makefile goals using regular expressions. Simplify your parsing with practical tips.
---
This video is based on the question https://stackoverflow.com/q/62879969/ asked by the user 'Kaimin' ( https://stackoverflow.com/u/6034435/ ) and on the answer https://stackoverflow.com/a/62883774/ provided by the user 'MadScientist' ( https://stackoverflow.com/u/939557/ ) at 'Stack Overflow' website. Thanks to these great users and Stackexchange community for their contributions.

Visit these links for original content and any more details, such as alternate solutions, latest updates/developments on topic, comments, revision history etc. For example, the original title of the Question was: How to escape and print forward slash in Makefile's goals names by regular expression?

Also, Content (except music) licensed under CC BY-SA https://meta.stackexchange.com/help/l...
The original Question post is licensed under the 'CC BY-SA 4.0' ( https://creativecommons.org/licenses/... ) license, and the original Answer post is licensed under the 'CC BY-SA 4.0' ( https://creativecommons.org/licenses/... ) license.

If anything seems off to you, please feel free to write me at vlogize [AT] gmail [DOT] com.
---
How to Effectively Escape and Print Forward Slash in Makefile's Goal Names Using Regular Expressions

When working with Makefiles that contain multiple goals, particularly those involving slashes, you might encounter some challenges in parsing and sorting these commands. If you’re trying to extract help details from included .mk files but struggling with proper formatting, especially when it comes to slashes, this guide is for you. Let’s explore how you can efficiently handle slashes in Makefile goal names using regular expressions (regex).

The Problem: Parsing Makefile Goals with Slashes

You may run into issues when attempting to parse Makefiles with goals that include forward slashes, such as docker/ps or docker/machine/ps. While your current setup works great for regular goals, escaping the slash can be tricky. Many scripts likely filter goal names with a regular expression that does not account for slashes, leading to incomplete or incorrect help command outputs.

Example Makefile Goals

Here are some sample Makefile targets to illustrate the challenge:

[[See Video to Reveal this Text or Code Snippet]]

Your Current Approach

You may already be using a grep command similar to this:

[[See Video to Reveal this Text or Code Snippet]]

However, the regex here doesn’t account for slashes in target names. So, how can you fix that?

The Solution: Adjusting the Regex

To rectify this issue, you need to extend your regex to allow slashes. Here’s a step-by-step breakdown:

1. Modify the Character Class

The simplest modification is to adjust the character class in your grep command. Instead of using:

[[See Video to Reveal this Text or Code Snippet]]

You should modify it to:

[[See Video to Reveal this Text or Code Snippet]]

2. Removing Non-Greedy Matching

You might be using .*? in your regex expecting non-greedy matching. However, Extended Regular Expressions (EREs) in grep don’t support non-greedy matching. You can simply use .* without the question mark, which serves your purpose here without being restrictive.

3. Suggested Command

Putting it all together, your updated grep command would look like this:

[[See Video to Reveal this Text or Code Snippet]]

Benefits of Allowing Slashes

By enabling slashes in your goal names, you enhance the readability and organization of your commands. Here are the key advantages:

Autocomplete Efficiency: Using slashes allows for better structure in make targets, making it easier to navigate and autocomplete.

Improved Help Command Output: More inclusive regex means your help command will capture all relevant targets, providing a complete reference.

Conclusion

Properly parsing Makefile goals that include slashes is straightforward with the right regular expression adjustments. By following the steps outlined above, you can ensure that your Makefiles are fully functional, user-friendly, and capable of providing the assistance you need when executing commands.

With these improvements, you’ll not only streamline your scripting process but also enhance the experience for anyone using your Makefiles. Happy coding!