Description:
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Within a namespace, set_error_handler($callable) tries to resolve $callable against this namespace, if $callable is a simple string.

This is inconsistent to other PHP-APIs, which do not resolve static global functionnames against the current namespace.



Test script:
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<?php
namespace Foo;
function handle() {}
set_error_handler('handle');

Expected result:
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# no error, warning etc. at all

Actual result:
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PHP Warning:  set_error_handler() expects the argument (handle) to be a valid callback