Re: regexp question

["Florian Kaufmann" <sensorflo@gmail.com>]

>  i want to replace a block beginning with <column_right> and ending with
> </column_right>, with a variable number of lines between with another
> text block. ext block with a regular expression?

I would use:

<column_right>\(.\|^J\)*?</column_right>

Where the ^J results from pressing C-q C-j.

The details: Since the dot . does much any character but the newline, I
use the construct \(.\|^J\) which now matches really any character. *?
is the lazy version of the greedy *. Meaning that as few as possible
are selected. This prevents from selecting too much. Only * instead of
*? would much both of the following lines instead of only one.

<column_right>line1</column_right>
<column_right>line2</column_right>

However, my regex fails to match nested tags. In the following example
<column_right><column_right></column_right></column_right>

the match is
<column_right><column_right></column_right>

which is not what you want. I don't know how to make a regular
expression which would also support this case. I'm sure you would find
the answer in the book "Mastering regular expressions"

Flo