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Reformatting reordered LaTeX paragraphs in Vim @ 07 Mar 2015

While revising a non-technical paper in LaTeX recently, I found it useful to reorder the sentences in some paragraphs to improve the flow and meaning of the text. In doing this, I often manually deconstructed the text into separate sentences in the source to make reordering easy.

As an extreme example, I would go from this:

Lorem ipsum dolor sit amet, consectetur adipiscing elit. In pulvinar
neque nec odio auctor ultricies. Ut maximus libero nibh, eget tempus
nulla convallis nec. Ut auctor, augue eget ornare tincidunt, leo risus
porta eros, id auctor metus mauris sit amet turpis. Nullam malesuada
pharetra nunc, sed faucibus velit rhoncus ut. Aliquam sagittis gravida
elit ut convallis. Sed auctor, ipsum in malesuada tempus, urna nunc
hendrerit quam, sit amet tincidunt purus turpis ut ipsum. Nam vel augue
blandit, hendrerit mi sed, tempus arcu.  Suspendisse metus magna,
placerat ut vulputate sed, vehicula eget nisl. Nulla gravida, erat non
pretium efficitur, ligula sem consequat sem, vitae mattis tellus lectus
in diam. Aenean in luctus velit. Cras lacinia lorem eget euismod
faucibus.

To this (sentences in question starting on newlines):

Lorem ipsum dolor sit amet, consectetur adipiscing elit.
In pulvinar
neque nec odio auctor ultricies.
Ut maximus libero nibh, eget tempus
nulla convallis nec.
Ut auctor, augue eget ornare tincidunt, leo risus
porta eros, id auctor metus mauris sit amet turpis. Nullam malesuada
pharetra nunc, sed faucibus velit rhoncus ut.
Aliquam sagittis gravida
elit ut convallis. Sed auctor, ipsum in malesuada tempus, urna nunc
hendrerit quam, sit amet tincidunt purus turpis ut ipsum. Nam vel augue
blandit, hendrerit mi sed, tempus arcu.  Suspendisse metus magna,
placerat ut vulputate sed, vehicula eget nisl. Nulla gravida, erat non
pretium efficitur, ligula sem consequat sem, vitae mattis tellus lectus
in diam. Aenean in luctus velit. Cras lacinia lorem eget euismod
faucibus.

Then to this (some sentences reordered):

Lorem ipsum dolor sit amet, consectetur adipiscing elit.
Ut auctor, augue eget ornare tincidunt, leo risus
porta eros, id auctor metus mauris sit amet turpis. Nullam malesuada
pharetra nunc, sed faucibus velit rhoncus ut.
Ut maximus libero nibh, eget tempus
nulla convallis nec.
In pulvinar
neque nec odio auctor ultricies.
Aliquam sagittis gravida
elit ut convallis. Sed auctor, ipsum in malesuada tempus, urna nunc
hendrerit quam, sit amet tincidunt purus turpis ut ipsum. Nam vel augue
blandit, hendrerit mi sed, tempus arcu.  Suspendisse metus magna,
placerat ut vulputate sed, vehicula eget nisl. Nulla gravida, erat non
pretium efficitur, ligula sem consequat sem, vitae mattis tellus lectus
in diam. Aenean in luctus velit. Cras lacinia lorem eget euismod
faucibus.

With the sentences reordered, I needed to reformat the source to restore the clean style seen in the first example. Those familar with Vim likely think of gq, which reformats the selected source. To help further, vip will visually select the paragraph! So, what about vipgq?

Lorem ipsum dolor sit amet, consectetur adipiscing elit.  Ut auctor,
augue eget ornare tincidunt, leo risus porta eros, id auctor metus
mauris sit amet turpis. Nullam malesuada pharetra nunc, sed faucibus
velit rhoncus ut.  Ut maximus libero nibh, eget tempus nulla convallis
nec.  In pulvinar neque nec odio auctor ultricies.  Aliquam sagittis
gravida elit ut convallis. Sed auctor, ipsum in malesuada tempus, urna
nunc hendrerit quam, sit amet tincidunt purus turpis ut ipsum. Nam vel
augue blandit, hendrerit mi sed, tempus arcu.  Suspendisse metus magna,
placerat ut vulputate sed, vehicula eget nisl. Nulla gravida, erat non
pretium efficitur, ligula sem consequat sem, vitae mattis tellus lectus
in diam. Aenean in luctus velit. Cras lacinia lorem eget euismod
faucibus.

While that looks nice at quick glance, further inspection reveals that there are two spaces between certain sentences. Some additional Vim commands can clean that up, but it's even easier if one introduces a command to accomplish the task. I added the following to my Vim configuration:

map <C-e> vipgqgv:s/ \{2,\}/ /g<CR>:noh<CR>

Now, <C-e> will do several things:

  1. Select the paragraph under the cursor (vip)
  2. Reformat the paragraph source as illustrated above (gq)
  3. Reselect the paragraph (gv, which re-selects the previous visual selection)
  4. Replace multiple spaces with a single space (:s/ \{2,\}/ /g<CR>)
  5. Clear the search pattern (:noh<CR>)

(That last item is important because I don't want Vim to highlight all occurrences of multiple spaces should I have space indents and the like elsewhere in my source.)

Using <C-e> on the reconstructed paragraph yields the following:

Lorem ipsum dolor sit amet, consectetur adipiscing elit. Ut auctor,
augue eget ornare tincidunt, leo risus porta eros, id auctor metus
mauris sit amet turpis. Nullam malesuada pharetra nunc, sed faucibus
velit rhoncus ut. Ut maximus libero nibh, eget tempus nulla convallis
nec. In pulvinar neque nec odio auctor ultricies. Aliquam sagittis
gravida elit ut convallis. Sed auctor, ipsum in malesuada tempus, urna
nunc hendrerit quam, sit amet tincidunt purus turpis ut ipsum. Nam vel
augue blandit, hendrerit mi sed, tempus arcu. Suspendisse metus magna,
placerat ut vulputate sed, vehicula eget nisl. Nulla gravida, erat non
pretium efficitur, ligula sem consequat sem, vitae mattis tellus lectus
in diam. Aenean in luctus velit. Cras lacinia lorem eget euismod
faucibus.
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