http://www.perlmonks.org?node_id=1052152


in reply to Re: strange usage of s///
in thread strange usage of s/// [solved: Perl 5.14 and 5.16 bug]

s/.././gr will convert each consecutive pair of any character (aside from newline) to single dots. If there's an extra (odd) character at the end, this won't be converted, but we don't worry about that because the input seems always to be strings of even numbered length.

Also, don't forget the importance of /r here, as it causes the substitution to return its result without modifying the original string, which is important since we're still working with the original string in the outer layer.


Dave

Replies are listed 'Best First'.
Re^3: strange usage of s///
by brx (Pilgrim) on Sep 03, 2013 at 20:35 UTC
    #!perl -pl s/@{[s".."."gr]}\K$"//

    I understand the regex like this:

    s/....\K // (with the good number of '.')

    ...but in facts it works like this:

    s/....\K/ /

    I don't understand why. The usage of $" seems magic too...

    English is not my mother tongue.
    Les tongues de ma mère sont "made in France".