# Extra character after pasting yank text into command line

I have a line of vimscript in my buffer like:

call MyFooFunction(1,2)


and I'm trying to execute it quickly.

So, I yank it (yy), invoke the command line (:), and paste it in with <C-r>"

But, after I paste, I see an extra ^M at the end:

:call MyFooFunction(1,2)^M


What is this extra ^M character and how do I not have it included when I paste?

That extra character is a newline. yy copies both the contents of the line and the line break. To copy a line without the line break, you can do 0y$. 0 moves to the beginning of the line, and y$ yanks until the last character of the line. If you want to, you could map it to make it faster:
nnoremap Y 0y\$

Y is a synonym for yy by default, so it is okay to map over it. You can map it to whatever key you prefer though.