Ok, I think I did not understand the original problem. I thought you were trying to 'align' all the comments from a text like this:

perl -E"say '.' x rand(80) . '# test comment' for 1..3"
......................# test comment
.................................# test comment
......................................................................
+....# test comment

[download]

So eventually I came up with this which I think is too complex. 

perl -E"say '.' x rand(80) . '# test comment' for 1..10" |perl -lpe " 
+/\s*#(.*)$|$/ && ( substr(  $_, $-[0], length($_) ) = qq{ }x(68 - $-[
+0] + 2) . qq{ #$1} )
...............................................                       
+ # test comment
..........................................................            
+ # test comment
.......................................                               
+ # test comment
............................................................          
+ # test comment
......................................................................
+.... # test comment
......                                                                
+ # test comment
........................................                              
+ # test comment
...............................                                       
+ # test comment
...................................................                   
+ # test comment
...................................                                   
+ # test comment

[download]

Maybe it can be rewritten with a printf but I will leave it with this.

In reply to Re^3: One-liner to append text at fixed column by Veltro
in thread One-liner to append text at fixed column by LanX

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":


  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.