See perlrun, there "paragraph mode". The boundary between paragraphs in that mode may comprise several blank lines.

Given a file named "text" as follows 

this is the first paragraph.
It has three lines.
Of which this one is the third.

A blank line denotes a paragraph. This one
has got two lines only.



The third paragraph is preceded with several
 blank lines, and it has itself
  three,
   no, wait, four lines.

Last paragraph. All paragraphs  should be shown
    each as
one line running "perl -p00 -le 's/\n/ /gs;s/\s+/ /g;'"
on that file, with multiple blanks condensed into one.

[download]

the snippet

perl -p00 -le 's/\n/ /gs;s/\s+/ /g;' text

[download]

does what you want. If you want inplace-edit (see perlrun again), say

perl -p00 -i.bak -le 's/\n/ /gs;s/\s+/ /g;' text

[download]

to have the file backed up with the suffix .bak as text.bak

You can provide multiple files on the command line; each will be processed in turn (and backed up, if requested).

In reply to Re: Can't remember the term to search for help on! (paragraph mode) by shmem
in thread Can't remember the term to search for help on! by tom2112

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