Named arguments

[stvowi]

How about it to implement named paramerters for functions / procedures such like in PHP8?

Named parameters in PHP allow you to pass arguments to a function based on the parameter names rather than their positions. This feature was introduced in PHP 8.0 and helps make function calls more readable and less error-prone.

<?php
declare(strict_types=1); // Enforce strict type checking

function create_anchor(string $text, string $href = '#', string $title = '', string $target = '_self') {
   $href = $href ? sprintf('href="%s"', $href) : '';
   $title = $title ? sprintf('title="%s"', $title) : '';
   $target = $target ? sprintf('target="%s"', $target) : '';
   return "<a $href $title $target>$text</a>";
}

// Using named parameters...

$link = create_anchor(
   text: 'PHP Tutorial',
   href: 'https://www.phptutorial.net/',
   target: '_blank'
);
echo $link;

In this example, the create_anchor function creates an anchor () element. By using named parameters, you can specify only the arguments you want to change, making the code more readable.

Important Considerations

Skipping Default Arguments

Named parameters allow you to skip default arguments. For instance, if you only want to change the target parameter, you don't need to specify the default values for href and title.

Mixing Named and Positional Arguments

You can mix named and positional arguments in a function call. However, named arguments must come after positional arguments.

$link = create_anchor(
   'PHP Tutorial',
   'https://www.phptutorial.net/',
   target: '_blank'
);

Error Handling

Passing the same parameter multiple times or placing named arguments before positional arguments will result in an error.

Named parameters enhance code readability and reduce the likelihood of errors by allowing you to specify only the necessary arguments.

@see also: Php Functions

[stvowi]

That is my comment to the roadmap item: named arguments - set argument(s) by name, including the Nth one without the preceding args. Open question: must the skipped args have declared defaults, or are they zeroed? Needs discussion.

I hope you meaned named argumends by functions/ procedures.

[fibodevy]

Named arguments are on the roadmap (#3), so this will land at some point. I am not giving a timeline.

Yes, functions and procedures.

Your open question is exactly the part I am still weighing. Two ways to go:

• a skipped parameter that has no declared default gets zeroed, the way the zeroinit modifier zeroes locals in a routine
• skipping is allowed only for parameters that carry a default, so anything without one still has to be passed, positionally or by name

The first is more permissive, the second keeps a missing argument an error instead of silently handing the routine a zero. Not decided yet.

The rest matches what I would expect for Pascal too: named arguments after positional ones, no duplicates.

[stvowi]

this is a nice feature