Returning to this example below…

s/(?<=look)(?=ahead)/-/g;

…assume “look” and “ahead” are on separate lines one below the other. Then the line becomes this…

s/(?<=look)\n(?=ahead)/-/g;

Is there some restriction, as the two words do not get joined with a dash? (At least for me)

Plus, there is no error message; the command just doesn’t work. My one-liner is below. I’ve ensured my apostrophe’s are correct after I copy/paste; plus, I’ve key-stroked every character, and tried numerous variations, etc., etc. Using Mac OS Sequoia 15.0 and perl 5.34.

perl -i -pe ’s/(?<=look)\n(?=ahead)/-/g;’ myfile.txt

In reply to Re: Using Look-ahead and Look-behind by akiemr19
in thread Using Look-ahead and Look-behind by Roy Johnson

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