How to Use the Command 'tidy' (with Examples)
Tidy is a versatile command-line tool designed to clean up and pretty print HTML, XHTML, and XML files. It is a helpful utility for developers and web designers who need to ensure their files are structured correctly and adhere to standard formatting guidelines. While Tidy enhances the readability of these documents, it should be noted that it cannot preserve the original indentation in its output. Tidy is especially useful in improving the quality and presentation of code, making it more maintainable and easier to navigate.
Use case 1: Pretty Print an HTML File
Code:
tidy path/to/file.html
Motivation:
When working with HTML files, especially those that have been minified or poorly formatted, it can be difficult to read and understand the structure of the document. Pretty printing an HTML file with Tidy enhances the readability by reformatting the code into a more human-friendly format. This makes the file easier to edit, debug, and maintain for developers.
Explanation:
tidy: This is the command itself, invoking the Tidy utility.path/to/file.html: This specifies the path to the HTML file that you wish to pretty print. You replacepath/to/file.htmlwith the actual path to your HTML file.
Example Output:
After running the tidy command, your HTML file might change from a condensed format like:
<html><head><title>Sample</title></head><body><h1>Hello World</h1></body></html>
To a more organized format such as:
<html>
<head>
<title>Sample</title>
</head>
<body>
<h1>Hello World</h1>
</body>
</html>
Use Case 2: Enable Indentation and Line Wrapping in an HTML File
Code:
tidy --indent y --wrap 100 -output path/to/output.html path/to/file.html
Motivation:
Indention and wrapping lines ensure that an HTML file adheres to a specific formatting standard, which is beneficial for collaboration among team members and future code maintenance. By setting line wrapping, long lines are broken down to a specified width, making it easier to read the code on various editors and interfaces without horizontal scrolling.
Explanation:
--indent y: This option tells Tidy to indent the output, making the document more readable with hierarchical formatting.--wrap 100: This argument limits the length of each line to 100 characters before wrapping to the next line, ensuring the code fits within standard editor windows.-output path/to/output.html: Specifies the output path for the new file. Tidy will write the prettified HTML file to this location.path/to/file.html: The original HTML file that you want to process.
Example Output:
An HTML file with initially inconsistent spacing and overly long lines like this:
<html><head><title>Page Title</title></head><body><p>This is a very long paragraph that exceeds the standard width of 100 characters which can make it hard to read or edit in various text editors without scrolling.</p></body></html>
Would be formatted into:
<html>
<head>
<title>Page Title</title>
</head>
<body>
<p>
This is a very long paragraph that exceeds the standard width of 100
characters which can make it hard to read or edit in various text editors
without scrolling.
</p>
</body>
</html>
Use Case 3: Modify an HTML File In-Place Using a Configuration File
Code:
tidy -config path/to/configuration -modify path/to/file.html
Motivation:
Sometimes, a specific style guide or project requirement necessitates using a custom set of configuration options for HTML formatting. Using a configuration file allows you to apply these options consistently across multiple files without specifying each option manually in the command line. This command modifies the original file directly, useful for batch processing or when you want to enforce a standard.
Explanation:
-config path/to/configuration: This option tells Tidy where to find the configuration file that contains specific formatting rules. This file may include various Tidy options set for your project needs.-modify: Instructs Tidy to modify the original file directly with the changes, as opposed to writing to a new output file.path/to/file.html: The path to the HTML file that you want to modify according to the configuration settings.
Example Output:
Suppose your configuration file specifies conditions for consistent spacing and specific attribute ordering. Using this command, a file like:
<p style="color:red;"class="example">Hello, World!</p>
Would be formatted directly within the same file as:
<p class="example" style="color:red;">
Hello, World!
</p>
Conclusion:
The tidy command is an indispensable tool for developers who deal with HTML, XHTML, and XML files. Through its various options, it enables users to make their code cleaner, more consistent, and ultimately more maintainable. The ability to reformat improperly structured files, enforce consistent indentation and line lengths, and apply customized formatting rules makes Tidy highly valuable in web development workflows.
