Finding first field duplicate lines in a sorted text file without uniq or awk or col using only vim - is it possible?

In alt.os.linux Arlen G. Holder wrote:

Did you already have that available, or did you expressly code it to
resolve the problem set?


I did not have it already. I tackled it as an exercise.


I'm curious, if you wrote that script, did you hand do it first inside of
VIM and then copied the hand code to the script? It's the most involved vim
script I've ever seen, which is why I ask.


Yes. I did the macro first as a series of commands in vim, then put
those commands into a register. The function stuff that controls the
running of the macro was of course done separately.

On Mon, 17 Jun 2019 13:58:38 +0000 (UTC), owl wrote:

I did the macro first as a series of commands in vim, then put
those commands into a register. The function stuff that controls the
running of the macro was of course done separately.

Hi owl,
That makes sense that you tried it as a series of commands in VIM.

So that your script is leveraged to as many people as possible,
I posted it yesterday to the other Windows newsgroups, namely:
o Windows XP http://tinyurl.com/windowsxp-general
https://groups.google.com/forum/#!topic/microsoft.public.windowsxp.general/sJmie_RGTow
o Windows 7 http://tinyurl.com/alt-windows7.general


I did not have it already. I tackled it as an exercise.

Ah. Wow. That's very helpful of you.
I, for one, am appreciative - since it "seems" easy - but it's not.

I very much THANK YOU for coding that example, which is the whole point of
Usenet, which is for everyone to bring what they can of value to share.

I will state that I have searched the net, ad infinitum, and have NEVER yet
found a solution to the stated problem set until you coded this up for us!
https://stackoverflow.com/questions/1915636/is-there-a-way-to-uniq-by-column
https://stackoverflow.com/questions/22849757/how-to-delete-duplicated-rows-based-in-a-column-value
https://unix.stackexchange.com/questions/104525/sort-based-on-the-third-column
https://stackoverflow.com/questions/17847799/sort-and-remove-duplicates-based-on-column
https://superuser.com/questions/416134/how-can-i-sort-objects-by-third-column-in-powershell
https://www.biostars.org/p/271720/
https://unix.stackexchange.com/questions/77406/sort-only-on-the-second-column
https://unix.stackexchange.com/questions/171091/remove-lines-based-on-duplicates-within-one-column-without-sort
https://www.unix.com/shell-programming-and-scripting/179059-remove-duplicate-lines-based-field-sort.html
https://stackoverflow.com/questions/17847799/sort-and-remove-duplicates-based-on-column
https://stackoverflow.com/questions/33265934/duplicates-in-an-unix-text-file-based-on-multiple-fields
https://superuser.com/questions/332268/windows-7-sorting-contents-of-a-file/332269
https://stackoverflow.com/questions/22306490/how-to-sort-csv-by-columns-using-batch-scripting
https://stackoverflow.com/questions/12850909/how-to-remove-duplicates-in-a-csv-file-based-on-two-columns
https://stackoverflow.com/questions/1450085/list-only-duplicate-lines-based-on-one-column-from-a-semi-colon-delimited-file
https://stackoverflow.com/questions/6438896/sorting-data-based-on-second-column-of-a-file
https://www.mathworks.com/matlabcentral/answers/278956-sort-matrix-based-on-unique-values-in-one-column
https://www.ultraedit.com/support/tutorials-power-tips/ultraedit/advanced-column-based-sort.html
etc.

This solution of yours is a KEEPER for sure!
o Thank you for bringing value to the Usenet potluck to share with all!