# RFC: Debugable Enums

- Status: Implemented (PHP 8.6)
- Authors: Daniel Scherzer, daniel.e.scherzer@gmail.com
- Date: 2026-03-12
- Version: 0.3
- Implementation: https://github.com/php/php-src/pull/21425
- Original: https://wiki.php.net/rfc/debugable-enums
- Page: https://externals.io/rfc/debugable-enums
- More for agents: search with https://externals.io/search.md?q={query} · RFCs at https://externals.io/rfc.md · JSON API at https://externals.io/api · documentation at https://externals.io/llms.txt

## Votes

### Allow __debugInfo() in enums? (closed)

Yes: 16 · No: 2 · Abstain: 5

Voters: alcaeus (Yes), alexandredaubois (Abstain), ashnazg (Yes), beberlei (Yes), bwoebi (Yes), crell (Yes), daniels (Yes), derick (Yes), galvao (Yes), ilutov (Abstain), kalle (No), kguest (Yes), klaussilveira (Yes), mbeccati (Abstain), narf (Yes), ocramius (No), pmjones (Yes), ralphschindler (Yes), ramsey (Yes), shivam (Yes), theodorejb (Abstain), thorstenr (Yes), timwolla (Abstain)

## Discussions on the mailing list

- [\[RFC\] \[Discussion\] Stringable Enums](https://externals.io/message/129540.md) — started on 2025-12-04, 9 messages
- [\[RFC\] \[Discussion\] Debugable enums](https://externals.io/message/130303.md) — started on 2026-03-13, 6 messages
- [\[VOTE\] RFC: Debugable Enums](https://externals.io/message/130533.md) — started on 2026-04-02, 2 messages

---

## Introduction

Enumerations (enums) were introduced in PHP 8.1 ([enumerations](https://externals.io/rfc/enumerations)). The RFC specified that magic methods other than `__call()`, `__callStatic()`, and `__invoke()` would not be permitted in enums, noting that most other magic methods involve state, which enum instances do not have. However, the exclusion also applies to `__debugInfo()`, which does not need to involve state. This RFC proposes allowing the `__debugInfo()` magic method on enums.

```php
<?php
 
enum Foo: string {
	case Bar = "Baz";
 
	public function __debugInfo() {
		return [__CLASS__ . '::' . $this->name . ' = ' . $this->value];
	}
}
 
var_dump(Foo::Bar);
 
?>
```

produces the output

```
enum(Foo::Bar) (1) {
  [0]=>
  string(14) "Foo::Bar = Baz"
}
```

## Proposal

The error when trying to implement `__debugInfo()` on an enumeration is removed. The default validation of that magic method (visibility, arguments, return type) is applied if the method is present.

### Examples

Simple example for a unit enum:

```php
<?php
 
enum Foo {
	case Bar;
 
	public function __debugInfo() {
		return [$this->name . ' is a case of the ' . __CLASS__ . ' enum'];
	}
}
 
var_dump(Foo::Bar);
 
?>
```

produces the output

```
enum(Foo::Bar) (1) {
  [0]=>
  string(29) "Bar is a case of the Foo enum"
}
```

Simple example for a backed enum:

```php
<?php
 
enum Foo: string {
	case Bar = "Baz";
 
	public function __debugInfo() {
		return [__CLASS__ . '::' . $this->name . ' = ' . $this->value];
	}
}
 
var_dump(Foo::Bar);
 
?>
```

produces the output

```
enum(Foo::Bar) (1) {
  [0]=>
  string(14) "Foo::Bar = Baz"
}
```

## Backward Incompatible Changes

There should be no backward incompatible changes - this is the removal of an existing error.

## Proposed PHP Version(s)

Next PHP version (PHP 8.6).

## RFC Impact

### To the Ecosystem

Analysis tools that warn about trying to define a `__debugInfo()` method on enums would need to be updated to not warn when the code is for PHP 8.6+.

### To Existing Extensions

There are some built-in enums, e.g. `\Random\IntervalBoundary` - in the future, they may have `__debugInfo()` methods, but this RFC does not include such additions.

## Future Scope

Perhaps some of the other magic methods should also be allowed.

## Voting Choices

Primary Vote requiring a 2/3 majority to accept the RFC:

**Vote: Allow \_\_debugInfo() in enums?** — Yes: 16 · No: 2 · Abstain: 5 (closed)

## Patches and Tests

## Implementation

<https://github.com/php/php-src/pull/21425>

After the RFC is implemented, this section should contain:

1. the version(s) it was merged into
2. a link to the git commit(s)
3. a link to the PHP manual entry for the feature

## References

Links to external references, discussions, or RFCs.

## Rejected Features

- Originally, an RFC proposed allowing `__toString()` on enums, rather than `__debugInfo()`, but feedback on the mailing list (<https://news-web.php.net/php.internals/129540>) led to a rewrite.

## Changelog

If there are major changes to the initial proposal, please include a short summary with a date or a link to the mailing list announcement here, as not everyone has access to the wikis' version history.

- v0.2: created (started from v0.2 since the `__toString()` version could be considered v0.1)
- v0.3: updated implementation to keep the `enum(Foo::Bar)` headers in the output, updated examples here to show the full output, minor editorial changes