Why Does `print_r` Output a '1' in PHP?

Unveiling the Mystery of "1" in PHP's print_r Output

When using PHP's print_r function to display the contents of an object or array, you may encounter an enigmatic number "1" appended to the end of the output. This seemingly innocuous character has sparked curiosity and confusion among PHP developers.

Understanding the Verbosity of print_r

print_r is a versatile function that offers adjustable verbosity levels for displaying data. The default verbosity level is 1, indicating that the function prints the data in a concise, human-readable format. However, if you explicitly specify print_r($var, true) with true as the second parameter, it will switch to verbose mode, revealing more detailed information about the data structure, including its type, allocation, and other specific attributes.

Echoing vs. Just Printing

When you execute print_r($var) without using echo, the function merely prints the data to the standard output stream. In this scenario, the number "1" you observed is not relevant to the output itself; it simply signifies the return value of print_r, which is the total number of bytes written to the output stream.

Echoing print_r

The situation changes when you echo print_r($var). This combination prints the output of the print_r function to the web page or console. In this context, the "1" becomes part of the displayed output alongside the data structure.

Resolving the Issue

To prevent the "1" from cluttering your output, you can simply omit the echo construct, allowing print_r to write the data directly to the output stream:

print_r($view);

By utilizing print_r appropriately, you can effectively display data structures, whether for debugging or visualizing complex objects and arrays. Remember, it's much more effective to focus on understanding the actual data rather than interpreting the technicalities of the output.

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