Description:
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Is possible to use namespace declaration inside a label. Is this correct?

And the error message could be changed, as 'use' and 'declare' (perhaps also 'label' declaration) statements can be used before him.

Reproduce code:
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<?php

foo:
namespace foo::bar;


Expected result:
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Fatal error: Namespace declaration statement has to be the very first statement in the script

Actual result:
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No error