How can copy the matched string into register +?

Question

For the below data:

-150000    2023-03-30
421.67     2023-04-20
575        2023-05-20

I can substitute the whole line with the first string

:%s/\v.{-1,}\s+(.+)/\1

Then the content was changed into:

-150000
421.67
575

I can copy the lines into register + with:

:%y+

With my method the primitive data was

-150000    2023-03-30
421.67     2023-04-20
575        2023-05-20

converted into

-150000
421.67
575

,then copy it and create a recovery with undo.

How can copy the matched string into register + without changing the previous lines ?

Answer 1

Let's first clear the + register, because we want to append to the clipboard (+) register:

let @+=''

Now we will use the setreg() function to append to the + register. Since we only want to work with the matched string, and don't want to actually do some substitution, you can use the n flag of the :s command.

%s/\v.{-1,}\s+(.+)/\=setreg('+',submatch(1),'aV')/ng

This runs your :s command, retrieves the submatch(1) from your pattern and operates on the match, while not substituting anything. This internally runs in the sandbox, so not all functions may be safe. But appending to a register should generally be safe.

Answer 2

Here is one way to achieve your goal:

qaq
:g/^/call setreg('A', expand('<cWORD>'), 'V')

• qaq starts a recording into register a and then immediately stops it, which is a handy way to empty register a. See :help recording.
• :[range]g/<pattern>/<command> executes <command> on every line in [range] that matches <pattern>. See :help :g.
• the <pattern>, ^, is a trick to match "every line",
• the <command>, call setreg('A', expand('<cWORD>'), 'V'), essentially tells Vim to append the current WORD to register a in linewise mode. See :help setreg() and :help WORD.

For register +:

:let @+=''
:g/^/call setreg('+', expand('<cWORD>'), 'Va')