Helm: How to properly enable helm-follow-mode

[tuhdo]

I want to enable helm-follow-mode in helm-occur and helm-multi-occur by doing so:

(add-hook 'helm-after-initialize-hook
          #'(lambda () (helm-attrset 'follow 1 helm-source-occur)))
(add-hook 'helm-after-initialize-hook
          #'(lambda () (helm-attrset 'follow 1 helm-source-moccur)))

It works fine in my running Emacs. However, after restarting Emacs, this error occurs:

Wrong type argument: consp, nil

How do I setup properly?

[thierryvolpiatto]

tuhdo [email protected] writes:

How do I setup properly?

You can either:
1) set `helm-follow-mode-persistent' to non--nil.
Then after running helm-occur/moccur once it will be persistent.
2) Use C-/ (It is not helm-follow-mode though)
3) Use helm-attrset in your init file after loading helm-regexp.
(Use with-eval-after-load)

Thierry
Get my Gnupg key:
gpg --keyserver pgp.mit.edu --recv-keys 59F29997

[thierryvolpiatto]

I am closing this, please ask such questions on mailing list.
Thanks.

[tuhdo]

eval-after-load "helm-regexp" .... doesn't work. I always got the error because the helm-source-occur does not exist. I had to initialize the source and add follow-mode like this:

(helm-occur-init-source)

(helm-attrset 'follow 1 helm-source-occur)
(helm-attrset 'follow 1 helm-source-moccur)

I think when helm-regexp is loaded, it should initialize all sources.

But thanks for your advise.

[shea-parkes]

For anyone else that ends up here, not all of the helm sources have initialization functions. In particular, it can make a lot of sense to turn on follow-mode for helm-source-grep, but helm-source-grep is initialized to nil instead of a dummy source. I ended up going with this to get always-on follow-mode for greps:

(setq helm-source-grep (helm-build-dummy-source "init_grep" :follow 1))
(add-hook 'helm-before-initialize-hook
          (lambda () (helm-attrset 'follow 1 helm-source-grep)))

I imagine the :follow 1 is superfluous, but I'm too worn out after chasing this down to confirm/understand that well enough.

[thierryvolpiatto]

skparkes [email protected] writes:

For anyone else that ends up here, not all of the helm sources have
initialization functions. In particular, it can make a lot of sense to
turn on follow-mode for helm-source-grep, but helm-source-grep is
initialized to nil instead of a dummy source.

It is not the way to do, dummy sources are not for this.

I ended up going with this to get always-on follow-mode for greps:

(setq helm-source-grep (helm-build-dummy-source "init_grep" :follow 1))
(add-hook 'helm-before-initialize-hook
(lambda () (helm-attrset 'follow 1 helm-source-grep)))

This hack would work only for grep, please see:

https://github.com/emacs-helm/helm/wiki/FAQ#why-is-a-customizable-helm-source-nil

For the documentation of helm-follow-mode, yes it is deprecated and
should be fixed.

For the helm grep case, I will commit a change that will allow you to
do only:

(defmethod helm-setup-user-source ((source helm-grep-class))
(set-slot-value source 'follow 1))

Will be ready soon.

Thierry

[thierryvolpiatto]

See also helm-follow-mode-persistent.

Thierry

[shea-parkes]

Thanks for your willingness to help out.

I did read about helm-follow-mode-persistent, but I believe that is for making follow-mode "sticky" between helm sessions. I actually don't want it "sticky", I want every helm-occur and helm-grep session to start with follow-mode enabled (even if it was disabled at the end of the last corresponding helm session).

I'll try to read more about helm-setup-user-source now. My elisp prowess is weak, but I can usually (eventually) follow along.

I personally find follow-mode quite helpful when searching through file/buffer contents, but I did not feel like installing the third party helm-swoop just to get that functionality when it was already in helm core.

Thanks for maintaining a very helpful package.

[michael-heerdegen]

(with-eval-after-load 'helm-regexp
  (setq helm-source-occur
        (helm-make-source "Occur" 'helm-source-multi-occur
          :follow 1)))

[blaenk]

For what it's worth, this no longer works recently.

cl-no-applicable-method: No applicable method: make-instance, helm-source-multi-occur, "Occur", :follow, 1

[thierryvolpiatto]

Jorge Israel Peña [e-mail] writes:

For what it's worth, this no longer works recently.

cl-no-applicable-method: No applicable method: make-instance, helm-source-multi-occur, "Occur", :follow, 1

Because helm-source-multi-occur doesn't exists anymore, see issue #2146.

--
Thierry

[blaenk]

Nice, thanks for letting me know!

[thierryvolpiatto]

Now follow-mode is enabled by default in multi occur so you should not have to add some extra config.