This is from a memory of a discussion I couldn't find and this is just an outline but I think it'll work and be safe (someone will surely shoot that down if it's wrong). 

# Read the file.
# Inject 'BEGIN { exit }' at the beginning.
# Run 'perl -ce' on the text.
# Catch the output (eg, IO::CaptureOutput, Capture::Tiny).
# Look for "syntax OK"

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As mentioned, there are a few things that might not actually be Perl that'll parse fine as Perl.

In reply to Re: Recognizing Perl in text by Your Mother
in thread Recognizing Perl in text by Anonymous Monk

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