Re: Adding String to Beginning of Lines

[Christopher Dimech <dimech@gmx.com>]

> Sent: Wednesday, November 11, 2020 at 3:07 PM
> From: tomas@tuxteam.de
> To: help-gnu-emacs@gnu.org
> Subject: Re: Adding String to Beginning of Lines
>
> On Wed, Nov 11, 2020 at 02:22:44PM +0100, Christopher Dimech wrote:
> >
> > > Sent: Wednesday, November 11, 2020 at 12:16 PM
> > > From: "Michael Heerdegen" <michael_heerdegen@web.de>
> > > To: help-gnu-emacs@gnu.org
> > > Subject: Re: Adding String to Beginning of Lines
> > >
> > > <tomas@tuxteam.de> writes:
> > >
> > > > But watch out: the replacement string (confusingly called `regex' here,
> > > > others have already pointed that out) might contain special sequences
> > > > (e.g. "\\&") which have a meaning in this context.
> > >
> > > Indeed, an important objection.
> > >
> > > I would suggest to avoid using any query-replace at all and rather use
> > > something like
> > >
> > > #+begin_src emacs-lisp
> > > (save-excursion
> > >   (while (and (<= (point) end)
> > >               (not (eobp)))
> > >     (insert my-string)
> > >     (forward-line +1))
> > >   (deactivate-mark))
> > > #+end_src
> >
> > That's what I started doing at the beginning.  Should we revert to this
> > or continue with replace-regexp.  Have now removed the confusingly called
> > `regex' and it is currently called nwltok.
>
> If it's always the beginning of line you're inserting at, your first
> approach seems to make more sense.
>
> Something like
>
>   (beginning-of-line) ; if you aren't already there, see below
>   (insert "foo")
>
> should do what you're after.

Correct. Always at beginning of line

> The beginning-of-line isn't necessary if your advance function
> puts you already there. Note that (beginning-of-line 2) will
> put you at the beginning of the /next/ line.
>
> Cheers
>  - t
>