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in reply to Re: grep question using multiple lines
in thread grep question using multiple lines

Use the modifier notation might be of great style as well,

perl -nle 'print $1 while /constant=(.*)\s/g' /home/jamie/txt

But I remark the association of -l and \s vs. a more explicite regexp does not behave well in case of many matches on the same line!

Try it for example with a txt file as follow,

xxxxxxxxx constant=foo@bar.com xxxxxxxxxxx xxxxxx constant=baz@huux.org xxxxxxx contant=hello@world.bye xxxxxxxxx xxxxxxxxxxxxxxxxxxx

will print,

foo@bar.com baz@huux.org xxxxxxx contant=hello@world.bye

I think the problem comes from (.*) that is greedy and matches even spaces at the condition there is at least one space remaining to satisfie \s. But I try (.*?) and the /g flag does not seem ok?

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Re^3: grep question using multiple lines
by skx (Parson) on Dec 28, 2008 at 12:53 UTC

    Indeed your match is greedy. Still we can change it as follows:

    $ perl -nle 'print $1 while /constant=(^ +)\s/g' < test.txt
    barney@gmail.com
    wilma@aol.com
    
    Steve
    --