Call to undefined function¶
Description¶
This happens when calling a function that is not defined.
There should be a function definition in the code, and that function must be included in the code before its call.
The function may be defined in a PHP extension, or its core: then, the function has no definition. Its existence may be checked with a call to get_defined_function()
, which lists all the functions, at the execution point.
The function might be defined in a different namespace, or its import might be missing.
Example¶
<?php
foo();
function foo() {}
?>
Solutions¶
Check the spelling of the function name.
Check the version of PHP, or its extensions: some functions are defined in specific versions, or later.
Check the namespace of the called function: it might not be available in the current namespace, or in the global namespace.
Check the use expression at the beginning of the file: the import expression might be missing.