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Named Arguments in PHP: When This Popular Feature Actually Makes Your Code Worse

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Introduction: The Named Arguments Trap

When PHP 8 introduced named arguments, developers celebrated. Finally, we could call functions with crystal-clear parameter names instead of confusing positional arguments! But here's what the tutorials don't tell you: named arguments can actually make your code harder to maintain, more brittle, and surprisingly less readable. If you're a junior developer who's been told that named arguments are always better, it's time to learn when this feature becomes a liability rather than an asset.

In this post, we'll explore the real-world problems that named arguments create, backed by practical PHP examples you'll encounter in everyday coding. Yes, named arguments have their place—but understanding when NOT to use them will make you a better developer.

The Verbosity Problem: When Clarity Becomes Clutter

Named arguments promise clarity, but they often deliver unnecessary verbosity that makes code harder to scan. Consider this simple example:

<?php
// With named arguments
$user = createUser(
    firstName: 'John',
    lastName: 'Doe',
    email: 'john@example.com',
    age: 28
);

// Without named arguments
$user = createUser('John', 'Doe', 'john@example.com', 28);
?>

The second version is immediately scannable. Your eyes move left to right, processing four simple values. The named argument version? You're reading twice as much text to extract the same information. For a function with obvious parameters like createUser(), the parameter names add noise, not clarity.

The Alternative: Use named arguments only when parameters aren't self-explanatory from context. If your function name and parameter order are intuitive, stick with positional arguments. Save the verbosity for truly ambiguous cases.

The Refactoring Nightmare You Don't See Coming

Here's a problem that bites junior developers hard: named arguments create a public API surface for your parameter names. Once other parts of your codebase use named arguments, you can't rename parameters without breaking everything.

<?php
// Your original function
function sendEmail($recipient, $subject, $body) {
    // Implementation
}

// Someone calls it with named arguments
sendEmail(
    recipient: 'user@example.com',
    subject: 'Welcome!',
    body: 'Thanks for signing up'
);

// Later, you want to rename for clarity
function sendEmail($to, $subject, $message) {  // BREAKS existing code!
    // Implementation
}
?>

With positional arguments, renaming parameters is trivial—just update the function signature. With named arguments scattered across your codebase, you've created a maintenance burden. You'll need to search and replace every call site, or maintain backward compatibility with deprecated parameter names.

The Alternative: If you must expose a public API, use an options array or a dedicated parameter object that can evolve without breaking changes. For internal functions, avoid named arguments entirely to maintain refactoring flexibility.

False Clarity: When Names Don't Actually Help

Named arguments give you a false sense of self-documenting code. Developers see parameter names and assume they understand what's happening—but names alone rarely tell the full story.

<?php
// Looks clear, right?
$result = processPayment(
    amount: 99.99,
    currency: 'USD',
    retry: true,
    timeout: 30
);

// But what does retry actually do?
// - Retry on network failure?
// - Retry on validation error?
// - Retry on insufficient funds?
// - How many times does it retry?

// What's timeout measured in?
// - Seconds? Milliseconds? Minutes?
?>

Named arguments create an illusion of understanding. You see retry: true and think "I get it"—but you're still guessing at the actual behavior. Proper documentation, clear function names, and well-designed abstractions provide real clarity, not just parameter labels.

The Alternative: Focus on writing functions that do one thing well with minimal parameters. If a function needs extensive configuration, consider the builder pattern or configuration objects with comprehensive documentation. Don't rely on parameter names to explain complex behavior.

When Named Arguments Actually Shine

To be fair, named arguments aren't inherently bad. They excel in specific scenarios:

• Functions with many optional parameters: When you have 5+ parameters and most have defaults, named arguments let you skip to the one you need.
• Boolean parameters: download(includeMetadata: true) is clearer than download(true).
• Configuration functions: Methods that accept numerous settings benefit from explicit naming.

The key is intentionality. Use named arguments when they genuinely improve comprehension, not as a default coding style.

The Performance Consideration Nobody Mentions

While the performance impact is usually negligible, named arguments do carry a small overhead. PHP must match argument names to parameters at runtime, whereas positional arguments map directly. For high-frequency functions in performance-critical code paths, this matters. It's not a reason to avoid named arguments everywhere, but it's worth knowing when you're optimizing hot paths.

Making Smarter Choices

Here's a practical framework for deciding when to use named arguments:

1. Ask: "Would a colleague understand this without names?" If yes, skip them.
2. Count your parameters: 1-3 parameters? Probably don't need names. 4+ with defaults? Consider it.
3. Check for booleans or numbers: These benefit most from explicit naming.
4. Consider the audience: Public libraries need stability; internal code needs flexibility.
5. Design first: If you're reaching for named arguments to make a messy function clearer, redesign the function instead.

Conclusion: Use Named Arguments Wisely

Named arguments are a powerful PHP feature, but like any tool, they can be misused. The developers who treat them as a universal solution end up with verbose, brittle codebases that are harder to refactor and maintain. The best developers I've worked with use named arguments sparingly—only when they genuinely improve code clarity without sacrificing maintainability.

As a junior developer, your instinct might be to use every new language feature you learn. Resist that urge. The mark of a mature developer isn't knowing all the features—it's knowing when not to use them. Named arguments should be a deliberate choice, not a default habit.

Focus on writing simple, well-named functions with intuitive parameter orders. When you do reach for named arguments, make sure you're solving a real problem, not just adding ceremony to your code. Your future self—and your teammates—will thank you.