Why Does `print_r` Output a '1' at the End?

Demystifying the Intriguing "1" at the End of PHP's print_r Output

When utilizing PHP's print_r function to inspect an object, you may encounter an enigmatic "1" appended to the end of the output. This obscure detail has puzzled many developers, leaving them seeking clarification.

Unveiling the Source

The "1" at the end of a print_r statement is not documented explicitly in the PHP manual. Upon closer examination, it becomes apparent that this is an artifact of the echo construct being used in conjunction with print_r. When echo is employed, it automatically appends a newline character at the end of the output. This newline is rendered as "1" in the context of a print_r statement.

The Print_r Function

PHP's print_r function provides a succinct representation of an object or array. It recursively traverses the input, displaying the values and types of the object's properties and the array's elements. The output format adheres to PHP's var_dump function, presenting data in a human-readable manner.

Best Practices

While print_r can be useful for debugging purposes, it is not recommended to rely on parsing its output. More structured and reliable alternatives exist for extracting specific data from objects or arrays. For instance, you could utilize PHP's var_export function or implement getter methods to retrieve individual properties.

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