Suggestion about string substitution

Question

Hi guys,
I have been asked to modify a bunch of html files exported by a program named...mindmeister I guess.
It is a sort of faq and it is structured this way so the user can jump from a faq to another easily.
Well, I have something like 100 files or more and in any file I have the navigation repeated.
So in any page on there are 100 same links to other pages i order to be able to navigate through.
I have been asked to insert another page. This is the second time I have being asked to modify this faq list.
This is not a problem for me. The first time I just used Dreamweaver and I inserted easily another file. And I'm going to use it again because I cannot see how to do the same thing easily and simply
I just was wondering how could I done this without Dreamweaver.
I could use sed, sure, but imagine putting this in sed sintax:
This is the part of the navigation I have to modify in every file.
<div class="maintopic">
<img src="Res/images/arrow.gif" alt=""><span class="unselect"><a href="Estinzionedirelazioni.html"> 4. Estinzione di relazioni </a></span>
</div>
<div class="subtopic">
<img src="Res/images/arrow.gif" alt=""><span class="unselect"><a href="Dapartediprocuratore.html"> 4.1 Da parte di procuratore </a></span>
</div>
<div class="subtopic">
<img src="Res/images/arrow.gif" alt=""><span class="unselect"><a href="Estinzionefineanno.html"> 4.2 Estinzione fine anno </a></span>
</div>
<div class="maintopic">
<img src="Res/images/arrow.gif" alt=""><span class="unselect"><a href="(NUOVO)FormularioA,ReT.html"> 5. (NUOVO) Formulario A, R e T </a></span>
</div>
Now suppose I wanted to add faq 4.3 Crappy hardcoded navigation due to crappy proprietary program unable to export the navigation as javascript
My new navigation should be this one:
<div class="maintopic">
<img src="Res/images/arrow.gif" alt=""><span class="unselect"><a href="Estinzionedirelazioni.html"> 4. Estinzione di relazioni </a></span>
</div>
<div class="subtopic">
<img src="Res/images/arrow.gif" alt=""><span class="unselect"><a href="Dapartediprocuratore.html"> 4.1 Da parte di procuratore </a></span>
</div>
<div class="subtopic">
<img src="Res/images/arrow.gif" alt=""><span class="unselect"><a href="Estinzionefineanno.html"> 4.2 Estinzione fine anno </a></span>
</div>
<div class="subtopic">
<img src="Res/images/arrow.gif" alt=""><span class="unselect"><a href="Crappy proprietary program.html"> 4.3 Crappy hardcoded navigation due to crappy proprietary program unable to export the navigation as javascript </a></span>
</div>
<div class="maintopic">
<img src="Res/images/arrow.gif" alt=""><span class="unselect"><a href="(NUOVO)FormularioA,ReT.html"> 5. (NUOVO) Formulario A, R e T </a></span>
</div>
How would you do this? Doing this in sed would be unconfortable and time consuming.
I can do this with dreamweaver easily by just using code substitution in all files and the specifying to substitute this:
<div class="subtopic">
<img src="Res/images/arrow.gif" alt=""><span class="unselect"><a href="Estinzionefineanno.html"> 4.2 Estinzione fine anno </a></span>
</div>
with this:
<div class="subtopic">
<img src="Res/images/arrow.gif" alt=""><span class="unselect"><a href="Estinzionefineanno.html"> 4.2 Estinzione fine anno </a></span>
</div>
<div class="subtopic">
<img src="Res/images/arrow.gif" alt=""><span class="unselect"><a href="Crappy proprietary program.html"> 4.3 Crappy hardcoded navigation due to crappy proprietary program unable to export the navigation as javascript </a></span>
</div>
I hope this is just my own and not unix filters limit.
This is just my curiosity. As I wrote before I can accomplish this task with dreamwaver, but I don't like much that approach.
I would like something more unix.
Edited because of errors notified by Procyon.
Last edited by ArchArael (2009-06-09 21:42:08)

Answer 1

I'm not sure how much simpler you expect to get than Procyon's example, to be honest.   It does exactly what you used to do (basic search and insert after).  What in your opinion would be more simple?
I can even expand it out and comment it for you to make it clearer:
for file in *.html; do # Process every html file in the current dir
sed -i '
/<div class="subtopic">/ { # If we see a line that looks like <div class="subtopic">, then perform the commands between { }
n; # Read in the following line from the file (ie <img src="blah blah...)
s/4\.2 Estinzione/&/; # Attempt to replace "4.2 Estinzione" with itself (ie. no end effect, performed for the sake of the next command)
T; # If the previous replacement failed, skip the remainder of the commands (ie. if "4.2 Estinzione" exists on this line, continue, otherwise stop)
n; # Read in the following line from the file (ie. </div>)
# The following 3 lines say "after the current line, insert this line"
a \ <div class="subtopic">
a \ <img src="Res/images/arrow.gif" alt=""><span class="unselect"><a href="Crappy proprietary program.html"> 4.3 Crappy hardcoded navigation due to crappy proprietary program unable to export the navigation as javascript </a></span>
a \ </div>
} # end of block of actions to execute when you see <div class="subtopic"> -- note, leave this quote-backslash here, it is necessary -->' \
$file # do the previous actions on the current HTML file
done
(note that this is still a valid sed script even with the comments - you could copy and paste this and it would run.