and let’s assume the following content of Bar.php:
// Bar.phpnamespaceOtherDir;useSomeDir\Foo;// This now conflicts the class OtherDir\Foo
If both files OtherDir/Foo.php and SomeDir/Foo.php are loaded in the
same runtime, you will see a PHP error such as the following:
PHP Fatal error: Cannot use SomeDir\Foo as Foo because the name is already in use in OtherDir/Foo.php
However, as OtherDir/Foo.php does not necessarily have to be loaded and the
error is only triggered if it is loaded before OtherDir/Bar.php, this problem
might go unnoticed for a while. In order to prevent this error from surfacing,
you must import the namespace with a different alias:
// Bar.phpnamespaceOtherDir;useSomeDir\FooasSomeDirFoo;// There is no conflict anymore.
The variable $content does not exist. Did you forget to declare it?
This check marks access to variables or properties that have not been declared yet. While PHP
has no explicit notion of declaring a variable, accessing it before a value is assigned
to it is most likely a bug.
Let’s assume that you have a directory layout like this:
and let’s assume the following content of
Bar.php
:If both files
OtherDir/Foo.php
andSomeDir/Foo.php
are loaded in the same runtime, you will see a PHP error such as the following:PHP Fatal error: Cannot use SomeDir\Foo as Foo because the name is already in use in OtherDir/Foo.php
However, as
OtherDir/Foo.php
does not necessarily have to be loaded and the error is only triggered if it is loaded beforeOtherDir/Bar.php
, this problem might go unnoticed for a while. In order to prevent this error from surfacing, you must import the namespace with a different alias: