Please explain this SED expression Post: 302508331

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Top Forums Shell Programming and Scripting Please explain this SED expression Post 302508331 by alister on Sunday 27th of March 2011 10:35:36 PM

03-27-2011

Registered User

That unwanted "<VirtualHost>" is there because the /VirtualHost>/ pattern matches both the opening and closing markup. That causes { /VirtualHost>/!{ $!{ N; bt } } to not be executed for the first line of the block, hence that first "<VirtualHost>" will always be emitted by the implicit print at the end of the sed script since -n is not used. This also means that there's a logic error: /name/d will attempt to find a match after the first line of each block in addition to after the full block has been accumulated (which is what is intended).

To fix this problem, tighten up the regular expressions. The following should be better (I am not writing it on one line since my sed does not support the gnu extensions which allow labels to be followed by anything other than a newline):

Code:

:t
/<VirtualHost>/,/<\/VirtualHost>/ {
    /<\/VirtualHost>/! {
        $! {
            N
            b t
        }
    }
    /name/d
}

Regards,
Alister

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graphics::primitive::insets

Graphics::Primitive::Insets(3pm)			User Contributed Perl Documentation			  Graphics::Primitive::Insets(3pm)

NAME

       Graphics::Primitive::Insets - Space between things

DESCRIPTION

       Graphics::Primitive::Insets represents the amount of space that surrounds something.  This object can be used to represent either padding
       or margins (in the CSS sense, one being inside the bounding box, the other being outside)

SYNOPSIS

	 use Graphics::Primitive::Insets;

	 my $insets = Graphics::Primitive::Insets->new({
	   top	   => 5,
	   bottom  => 5,
	   left    => 5,
	   right   => 5
	 });

METHODS

   Constructor
       new Creates a new Graphics::Primitive::Insets.

   Instance Methods
       as_array
	   Return these insets as an array in the form of top, right, bottom and left.

       bottom
	   Set/Get the inset from the bottom.

       equal_to
	   Determine if these Insets are equal to another.

       left
	   Set/Get the inset from the left.

       right
	   Set/Get the inset from the right.

       top Set/Get the inset from the top.

       zero
	   Sets all the insets (top, left, bottom, right) to 0.

AUTHOR

       Cory Watson, "<gphat@cpan.org>"

SEE ALSO

       perl(1)

COPYRIGHT &; LICENSE
       Copyright 2008-2010 by Cory G Watson.

       This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself.

perl v5.12.3							    2010-08-21					  Graphics::Primitive::Insets(3pm)

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