Helm mark functions do not move the cursor at the right column

[Ambrevar]

This is basically #709 which I believe was closed a bit early.

@thierryvolpiatto You said it is a detail, but there is a use case where the current behaviour is inconvenient.

Using standard Emacs, I can set a mark then move the cursor to create a selection. If only then I realize that the first mark is not at the right spot, I can rectify that with C-x C-x (exchange-point-and-mark).

Helm mark functions (e.g. helm-mark-or-exchange-rect) almost allows to do that, but the point is moved to the beginning of the column when exchanging point and mark.

This forces me to use two bindings (the original exchange-point-and-mark and helm-mark-or-exchange-rect for the general case) instead of one.

helm: 20170419.2242
OS: Arch Linux
Emacs: 25.2

[thierryvolpiatto]

Pierre Neidhardt <[email protected]> writes:

This forces me to use two bindings (the original exchange-point-and-mark and helm-mark-or-exchange-rect for the general case) instead of one.

Should work now how you are expecting. I don't know what is helm-mark-or-exchange-rect though. Thanks.

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-- Thierry Gpg Key fingerprint = 6CEC 7081 AB33 E251 4AB8 5FC2 28D1 7F53 59F2 9997

[Ambrevar]

Thanks!

Sorry for the confusion with helm-mark-or-exchange-rect, I forgot it was of my own:

(defun helm-mark-or-exchange-rect ()
  "Run `helm-all-mark-rings' or `rectangle-exchange-point-and-mark' if in rectangle-mark-mode."
  (interactive)
  (if rectangle-mark-mode
      (rectangle-exchange-point-and-mark)
    (helm-all-mark-rings)))

Let's forget that and use helm-all-mark-rings instead.

In terms of column position, it seems to work.
In terms of usability, it is still not quite superseding exchange-point-and-mark.

With exchange-point-and-mark:

• Mark
• Move the cursor to the desired position.
• exchange-point-and-mark to fix the initial mark.

With helm-all-mark-rings:

• Mark
• Move the cursor to the desired position.
• Mark again.
• helm-all-mark-rings
• select second entry and fix the initial mark.

The functions don't serve the same purpose, but I'm wondering if there is a way to supersede exchange-point-and-mark elegantly.

[Ambrevar]

I found a solution that seems to work pretty well:

(defun helm-all-mark-rings-before-mark-point ()
  "Call `helm-all-mark-rings' before pushing the former point to the mark ring.
In Transcient Mark mode, this allows for rectifying the initial mark."
  (interactive)
  (let ((pos (point)) )
    (helm-all-mark-rings)
    (push-mark pos)))

The workflow is as follows:

• Mark
• Move the cursor to the desired position.
• helm-all-mark-rings-before-mark-point
• Confirm and fix the initial mark.

Compared to Emacs original behaviour, it is only one more key press.

[thierryvolpiatto]

Pierre Neidhardt <[email protected]> writes:

In terms of usability, it is still not quite superseding exchange-point-and-mark.

The purpose of helm-mark-ring is to store visited positions to retrieve them quickly, I still don't understand what you want to do with `exchange-point-and-mark`.

With exchange-point-and-mark: * Mark * Move the cursor to the desired position. * exchange-point-and-mark to fix the initial mark.

If you want to save the new position why don't you hit C-space twice ? Note that all the helm search functions are saving position to mark-ring when leaving this position, before this recent change helm-mark-ring was doing this too we have to restore this, perhaps it is this that is missing for you ?

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-- Thierry Gpg Key fingerprint = 6CEC 7081 AB33 E251 4AB8 5FC2 28D1 7F53 59F2 9997

[thierryvolpiatto]

I pushed a change that save current position to mark-ring before jumping to a mark with helm-mark-ring, have a try. PS: Ensure you use the default value of `helm-goto-line-before-hook`.

…

-- Thierry Gpg Key fingerprint = 6CEC 7081 AB33 E251 4AB8 5FC2 28D1 7F53 59F2 9997

[Ambrevar]

The purpose of helm-mark-ring is to store visited positions to retrieve
them quickly, I still don't understand what you want to do with
exchange-point-and-mark.

Just that: using helm-mark-ring's functions to store point and then retrieving the last mark, thus effectively doing the same thing as exchange-point-and-mark.

If you want to save the new position why don't you hit C-space twice ?

Because as I detailed above, before commit b518c23 it was 1 more mark + 1 more selection in the helm buffer. Not convenient.

Note that all the helm search functions are saving position to mark-ring
when leaving this position, before this recent change helm-mark-ring was
doing this too we have to restore this, perhaps it is this that is
missing for you ?

Which recent change?

Anyways, this is exactly what was missing for me, it works well. Consider it solved!

[thierryvolpiatto]

Great, closing now.

Thanks.