Php: how to resolve "Cannot redeclare class" when there's no "previously declared"

Question

I want to test the phpDocumentor-alpha, and there's a problem that some people seems not to have:

# sudo pear uninstall phpdoc/phpDocumentor-alpha
uninstall ok: channel://pear.phpdoc.org/phpDocumentor-2.0.0a6
olivier@olivier-ubuntu ~/Documents/pizzas/dev # phpdoc --help
bash: /usr/bin/phpdoc: Aucun fichier ou dossier de ce type
# 
# sudo pear install --alldeps -f phpdoc/phpDocumentor-alpha
downloading phpDocumentor-2.0.0a6.tgz ...
Starting to download phpDocumentor-2.0.0a6.tgz (1,107,853 bytes)
..................................done: 1,107,853 bytes
install ok: channel://pear.phpdoc.org/phpDocumentor-2.0.0a6
# phpdoc --help
PHP Fatal error:  Cannot redeclare class phpDocumentor\Plugin\Core\Listener in /usr/share/php/phpDocumentor/src/phpDocumentor/Plugin/Core/Listener.php on line 194

Fatal error: Cannot redeclare class phpDocumentor\Plugin\Core\Listener in /usr/share/php/phpDocumentor/src/phpDocumentor/Plugin/Core/Listener.php on line 194
#

Ok, i can avoid that problem with:

if ( !class_exists('MTIHelperEstadosLocal') ) {...}

But this is just an ugly workaround. I'd like to know if there's a way to know where the declaration was firt (= which include or whatever).

Any idea?

It will help someone http://stackoverflow.com/questions/708140/php-fatal-error-cannot-redeclare-class/43345929#43345929 — Muhammad Shahzad, Apr 11 '17 at 12:29

score 10 · Accepted Answer · answered Jul 02 '12 at 09:45

10

Here's the simple solution:

print_r(get_declared_classes());

answered Jul 02 '12 at 09:45

Olivier Pons

15,363
26
117
213

Excellent, this showed me that the first include was from composers autoload. – Kit Sunde Apr 29 '14 at 08:06

score 3 · Answer 2 · answered Jul 29 '13 at 15:51

Depending on your OS, and how you have constructed the path to your document root, there may be an issue with capitals versus lower case letters in the path name. This often trips me up on large CMS projects such as drupal on Mac OSX

// Insert this debug code before require statement.
if (class_exists('classInQuestion')) {
  $reflector = new ReflectionClass('classInQuestion');
  echo $reflector->getFileName() . ' ' . $reflector->getStartLine() . "\n";
  echo $newClassFile;
  exit();
}
// Normal pre-existing require statement
require_once $newClassFile

score 2 · Answer 3 · answered Jul 05 '12 at 18:43

2

In the file {path-to-pear-directory}/PEAR/phpDocumentor/vendor/composer/ClassLoader.php, the line 150 is:

require $file;

symply change it to

require_once $file;

answered Jul 05 '12 at 18:43

Ranieri Valença

29
1

1

This does not "fix" the problem, it just stops it from happening with a workaround. User should find the problematic code and fix it, such as using "require" twice is bad coding, and likely a bad codebase design or structure. This should be addressed properly. This suggestion is a bit like using `@` to "resolve" warning or notice messages. – James Sep 12 '15 at 20:11

metzelder · Answer 4 · 2019-12-02T13:47:17.817

0

In addition to all answers, what you might do is to also consider php declared classes. For example dotnet. When i explicitly define a class named Dotnet for purpose of using Dotnet binaries, it throws an error with the first instance creation of the class.

If you are to use your own modified class other than php presents to you, you should give them distinguishable names.

edited Dec 02 '19 at 13:47

answered Dec 02 '19 at 09:47

metzelder

655
2
15
35

Php: how to resolve "Cannot redeclare class" when there's no "previously declared"

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