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Chris Weyl's Technical Blog

Fast Project Finding With fzf

fzf is a fantastic utility, written by an author with a history of writing useful things. He's also a vim user, and in addition to his other vim plugins he has created an "enhancement" plugin called fzf.vim.

One of the neat things fzf.vim does is make it easy to create new commands for fuzzy searches. If you're like me, you probably have some absurd number of project repositories you keep around and jump to, as necessary. Not everything is in the same directory (e.g. ~/work/), naturally, and with a laptop, desktop, and a couple other machines the less-frequently used repos may be where one least expects them to be — or not present at all.

It's not hugely annoying, just a sort of mild pain to have to spend several extra seconds doing a fuzzy search manually, rather than having fzf do it. But we do have fzf, and it's not difficult at all to build out a new search, so there's really no reason to keep on inflicting that pain.

Create a :Projects command

Let's create a new command in my vimrc, :Projects, that invokes fzf to search through all the different work directories I have.

What does this do?

  1. Defines a new vim command, :Projects

    No surprises here.

  2. Invokes fzf#run() to run a fzf search

    fzf#run() handle the actual execution and presentation of fzf, as well has dispatching the results back to the sink.

    fzf#wrap() is neat. It allows a command to take advantage of fzf.vim's option handling -- or not, by simply omitting it.

  3. Uses find to look for repositories

    We know roughly where to look(~/work/, ~/.vim/plugged) and how deep to look. Just about everything I do is backed by git, so we can look for repositories and return the parent of the found .git back to fzf.

    Note that the find invocation deliberately omits a -type d argument. I do use git workdirs, meaning .git may well be a file (a "gitlink").

  4. Calls out to rsrchboy#fzf#FindOrOpenTab() with the project selected

    The sink option tells fzf#run() what to do with the results. In our case we have provided fzf#run() with a callback function, but you can also use built-ins as sinks.

The callback "sink" function

In general, I use one tab per project (repository) in vim. For me, this is a nice balance of utility and sanity. It also allows me to do things like set t:git_dir and t:git_workdir to the git and workdir, respectively, of the repository associated with the tab.

Our callback function first attempts to find an open tab with the workdir requested; if found, it just switches to it and returns. (It should probably admonish me to read the tab line before invoking :Projects.)

If not found. the callback function invokes fzf#run() again. This time we use git ls-files to generate the source list for fzf, allowing us to pick a file to be opened by the given sink: tabe.

Hey, that wasn't too hard!

Easier than writing this post, I'd say ;)

Happy hacking!


First Post

...um, kinda. I'm switching over from wordpress to Statocles, and porting my older posts over.

Still, who can resist "first post!" ;)


No, use *my* DNS. (aka Netflix vs tunnelbroker.net)

Google DNS is being hardcoded into a significant number of devices now. Which is nice, because it pretty much always works.

...except when you're trying to use Netflix and you have a tunnelbroker IPv6 tunnel. Ugh.

So, this is a brief followup to Stupid OpenWRT tricks. Or maybe "Getting Netflix to work when your ISP doesn't support IPv6 yet" is a better way to put it...

Continue reading No, use *my* DNS. (aka Netflix vs tunnelbroker.net)...


Stupid OpenWRT ipv6 tricks

So, if you're like me you find yourself wondering why your broadband provider has a /32 IPv6 prefix assigned, and yet chooses not to use it, forcing one to either be IPv4-only (how 20'th century) or use an IPv6-over-IPv4 tunnel solution.

Fortunately there is a simple and free solution out there, courtesy of Hurricane Electric's rather fabulous tunnelbroker service. Obtaining an IPv6 prefix and setting up the tunnel is covered, extensively, so I won't go into it. It's also rather easy to set the tunnel up on an OpenWRT based router, like mine. The default setup is rather nice, but there are some changes you can make to your router configuration that will make it even nicer.

Continue reading Stupid OpenWRT ipv6 tricks...


Currying Patterns

One of the most dangerous books I've ever even partially read is MJD's Higher Order Perl. In particular, its description of subroutine currying -- that is, building more specific functions out of more general purpose ones -- is a pattern I find incredibly useful.

The other day I found myself writing a number of routines that were surprisingly similar... kinda. They all implemented a common pattern, but across routines that were rather... different. I found myself wistfully longing for the familiar pattern of currying, and then realized -- I'm working in PERL, DAMNIT.

This is part of recent work of mine, extending Test::Moose::More to use subtests where they make sense. Here I was able to curry one function -- _validate_subtest_wrapper() -- by passing it a reference to another function, that it then invokes.

Excellent. Life is easier, as it should be.