Projectile

Projectile is a popular project interaction library for Emacs. Here is it's official documentation.

Overview

Project means a groups of files together, especially code, accroding to the EmacsWiki CategoryProject page. Different project management libraries have different views of projects. As far as I know, a project will always have a root directory in which contains all project files. There are many Projectile alternatives,including CEDET, which seem like came out earlier and more advanced, but I haven't tried it yet. EmacsWiki recommends it is probably not useful to use both of them at the same time, for the same project. So I decided to try Projectile first.

My basic understanding of project management came from Sublime text. The feature I wanted most is the ability to goto anything in a project very quickly and search anything very quickly. Let's see how to install and use Projectile with these two questions in mind.

Install

Install projectile package from MELPA. Add the following lines to your init.el is good enough for me to go.

(projectile-mode +1)
(define-key projectile-mode-map (kbd "s-p") 'projectile-command-map)
(define-key projectile-mode-map (kbd "C-c p") 'projectile-command-map)
(setq projectile-completion-system 'helm)

Note:

1. the first line enables Projectile mode, it is the same as projectile-global-mode but the latter is deprecated.

2. The second line defines s-p as Projectile's keymap prefix, s means Super key here.

3. the third line defines another keymap prefx C-c p, in case of you don't have a usable Super key.

4. the last line change projectile's completion system from the default ido to helm, of course I happened have helm package insalled. helm is easy to configure for basic usage, but that's another story for another time.

   Enable helm as completion system is different than install the helm-projectile package. The latter which is also writen by Projectile's author offers a second level of intergration with helm, but I decided not to install it right now, becourse it seems like less maintained by the author and will add complexity. This indepth post explained how helm-projectile works, it should be readed before you try.

Enable s-p key bindings on Gnome desktop

I can use s-p on my Chrome book without any problem, the Super key on Chrome book is the magnifying glass key, however I can't use s-p key bindings on my Arch Linux Gnome desktop, because Super+p key is alread taken by Gnome.

After found this post, I realized Super + p is bounded to "Switch monitor" in Gnome. Go in the dconf-editor via the command "dconf-editor" in a terminal, then go at:

/org/gnome/mutter/keybindings/switch-monitor

and disable "use default value" and delete:

'<Super>p',

give me back s-p key in Emacs.

Basic Usage

Getting key bindings help with C-c p ? or C-c p C-h.

Execute M-x following projectile- to see all Projectile commands.

Project

A project is a basically folder, Projectile automatic detect projects, without any configuration.

• Add a project to projects list

  Every time we open a file, Projectile detect if it is inside a project using a set of practical rules, if a new project is recongnized, Projectile will add it to it's projects list.

  If the automatic detection fails, you can also add a .projectile project marker into the root directory to force the folder to be detected as a project.

• Delete a project in projects list

  When the projects list goes too larger, I'd like to remove unused project in it.

  M-x projectile-remove-known-project can remove a selected project.

  M-x projectile-clear-known-projects can clear the project list.

• Switch project

  C-c p p Switch project and execute projectile-find-file by default.

• Show projects in project list

  C-c p p is also a convenice way to show projects in the project list.

File

C-c p f or M-x projectile-find-file go to any files in current project. This is what I expected the most. Try it, it is very pleasant to use.

Grep

C-c p s g or M-x projectile-grep find any thing in all files in current project. Try it now, it is very easy to use. The problem is that it is not increasement searching which is not cool. But it is reliable and very fast -- because it use external find and grep tools, so I decided to get used to it.

Conclusion

I'm happy with my Projectile's settings right now. As time goes by, I may try some more advanced features when I needs it.