Source code filters are definitely not restricted to valid code. You could, for example, use a source filter to decrypt some encrypted source stream (see Filter::decrypt that comes with the module Filter::Util::Call for a demo implementation, if interested). In other words, the problem lies elsewhere :)

In reply to Re: Are codefilters always restricted to valid code? by almut
in thread Are codefilters restricted to valid code? by LanX

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