Comp Sci: (Li|U)nix: regular expressions part5: grep -P

Self-tutoring about grep and regex: the tutor explores grep -P: P is for Perl.

When it comes to regular expressions, it’s hard to beat Perl. grep -P supports Perl regular expressions, but it’s noted as “experimental.”

I tried it today with a file containing a postal code:

grep -P -i “[a-z]\d[a-z]\d[a-z]\d” testfile

It found the postal code no problem.

As I’ve mentioned: not all systems are the same. Therefore, that experiement may not bring the same success on a different one.

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