[clug] Circumflex

Scott Ferguson scott.ferguson.clug at gmail.com
Sun Aug 20 08:20:44 UTC 2017

On 20/08/17 17:33, Bryan Kilgallin (iiNet) via linux wrote:
> Thanks, Eyal:
>> I think that the '\d' notation is a Perl extension, so try
>>      grep -P ^\d'

Match on start of line followed by any digit
grep -P '^\d'
grep -P "^\d"

(I suspect the "" is incorrect, though it works).

> I was confused among versions of regular expressions! Discovering by
> trial and error. So to search for `-' I had to escape it with `\'.
> What Web resource explains standard, extended, and Perl variants?


or, look at the book I sent you (Chapter 7 is Perl, 8 is Java, 9 is .NET)
Page 144 covers the different engines.

Note that page 6 - 22 is just about egrep


Use curl and grep to get all the links from the wikipedia page"=
curl https://en.wikipedia.org/wiki/Regular_expression 2>&1 | grep -o -E
'href="([^"#]+)"' | cut -d'"' -f2

Re: searching man files. "man -k" is the equivalent of "apropos". To
brute force search man files use "man -K $searchterm" (warning - it will
may take a while. Or just open a man file and type "/" followed by the
searchterm - then press Enter for jump to the first match (if there is one).

Kind regards

    A: Because we read from top to bottom, left to right.
    Q: Why should I start my reply below the quoted text?

    A: Because it messes up the order in which people normally read text.
    Q: Why is top-posting such a bad thing?

    A: The lost context.
    Q: What makes top-posted replies harder to read than bottom-posted?

    A: Yes.
    Q: Should I trim down the quoted part of an email to which I'm reply


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