Thursday 4 October 2012

Typing to Yourself

I had an awesome time at PyConUK last weekend. I went to my first code dojo where I helped write a text-based adventure game (with a disturbing plot!), played with using Python on a RaspberryPi to access the GPIO, started a new Python module for my own use, and gave my second ever lightning talk, titled ‘Typing to Yourself’. This is 'the blog of the talk'.

What's this about then?

I’d started finding that IM chat logs often gave a lot of information, and often the timestamps were useful. The conversational nature of the chats also often gave subtle and useful clues about things such as confidence levels which a more formal report would lose. I started to think that it would be worth having that even if I wasn’t chatting to someone else. And so the madness started….

Typing to yourself. About stuff. Preferably as it happens, in ‘real time’ (is there another kind?). I suppose some people use Twitter like this, but I (and I'm sure my employer) like it that I keep at least some things to myself.

I've been doing this for a few months now, and got a single file with about 1300 lines of info I've been writing. Originally I cleared it out every few days, but then thought that maybe keeping it all around would be of some benefit.

Why Type to Yourself?


Record snippets of new knowledge

There are hundreds of small things I’ll find out about and then not look at again for 6 months. And chances are, I’ll forget all about them. It’s worth recording that sort of stuff. Things like pv, a new and useful iptables rule, the name of a nice vim colour scheme.

Decouple recording from reporting

Part of a knowledge-based job, where part of the task involves continual learning and researching, is that there is always the risk of going off into some blind alleys, dead-ends, or things more interesting than what you / I should really be working on. Chances are, even if it’s tangential to the work you / I should be doing, it’s still useful in itself, and worth recording. If I’ve just spent half an hour reading about ZeroMQ, I’ll include that. I might not record it in a list of training activities for the week though. It defers disclosure, allowing selection to take place at a later point. And therefore encourages more interesting and accurate reporting. By separating out recording from (for example) time reporting systems, we can post-process and filter that raw data later. Same thing as RAW and JPEG files from a camera; it’s not a bad thing to have the RAW data even if the end result is somewhat different. We are likely to be more honest if we type to ourselves, including feelings, distractions, etc, some of which will be useful at a later point.

Record why decisions were made

We make dozens of design decisions every day, and the vast majority of these seem obvious at the time. But there are some that aren’t ever obvious, and some that won’t be tomorrow even if they are now. Recording why we make the choices we do is important, even if just to force us to make them consciously. And it can be very useful to document dead-end design decisions which we try and ultimately give up on, in the hope of avoiding repeating them in the future.

Overcome creative blocks

Writer’s block affects programmers as well as novelists. Or at least it affects me from time to time. Sometimes I sit there for minutes on end, simply staring at the screen. I’ve found that explaining my dilemma to myself through the medium of typing to myself can often overcome this. Sometimes any activity can be a key to being able to think clearly about a problem again. Not only that, but regularly writing down what you're doing can be a great antidote to distraction and procrastination. This comes back to being able to be honest with ourselves about what we're doing - writing this down makes us think about it, be able to criticise it, and therefore more quickly be able to change direction.

Rubber duck debugging

© Tom Morris / Wikimedia Commons / CC-BY-SA–3.0 / GFDL

This is a technique which uses vocalisation of a problem we’re facing to make us think more clearly about the problem; to take a step back, and explain to a toy rubber duck - ideally one with no previous knowledge of the problem we’re facing - what’s going on and how we’re trying to fix it. Just explaining it often helps us realise the problem. But rubber ducks are tricky to find at the crucial moment, and people think programmers are mad enough already without seeing us all talking to little ducks sitting on our desks. No, typing to ourselves, writing down the problem, is clearly much safer. After all, a programmer writing down a problem to themselves looks highly productive, rather than slightly mad.

Searchable history

We version control our code. Why not version our thoughts and activities? Write stuff down. Be able to go back in time and revisit those thoughts at a later date. Use it to store our short-term thoughts just before a meeting or break, so picking up where we left of is easy. That sort of stuff. Or to record surprising errors which we can’t reproduce and just put down to ‘something must have been set up wrong’. But then we start to find that we’ve already recorded it two months earlier…

How should I go about that?


Timestamped

Typing to yourself is an activity best done in real-time. Doing it later may still have some benefit, but the stream of consciousness brain-dump in the background has a lot of value which is lost if we’re just typing a historical report on what happened earlier. The point of typing to yourself is that having a record is useful; trying to remember stuff to record after the fact is lossy and a waste of time. Having things timestamped is a motivation (‘I’ve not written anything for 2 hours!’) and useful for searching history - finding out just when that bug appeared last.

Centralised

For a given context (e.g. work), there should be a single log on which you type to yourself. Perhaps there shouldn’t even be multiple contexts; everything should go in one big fat log. But it should be a single log, and yet available everywhere. Having to merge logs, or wondering where the latest version is, or knowing but not having access to it - all bad things. Dropbox is good.

Low friction

The whole point of ‘typing to yourself’ is that it shouldn’t be a context switch. I tend to keep a tmux pane open with editfile running (as track -t). Switching into it is just a case of Ctrl-A/cursor key. Then type stuff. Then Ctrl-A/cursor the other way. There’s no alt-tabbing, no windows changing focus or popping in front of each other. And importantly, I can see what’s there at all times, so it’s always in my consciousness - I don’t have to ‘swap it back in’ when I switch to it. Another aspect of low-friction is that the data itself should be widely available to programs to use, whether for searching, editing, or anything else. A text file is ideal.

An Implementation

I’m more keen about the ideas here than the implementation, but without an implementation it couldn’t work. I use my editfile program for almost all longer pieces of writing - blog posts, ideas, plans. And my ‘typing to myself’ log, which is just an editfile ‘instance’ used in ‘time track’ mode, which keeps a single file on Dropbox with all the content in a text file. I wrote about editfile in an earlier blog post. editfile started out as a very simple bash script:

#!/bin/bash
$EDITOR "~/Dropbox/editfile/$(basename $0)"

but is now a more complex bash script, including search, a two level hierarchy (I had that before iCloud decided it was a good idea!), command-line completion, and the time track mode I use for typing to myself.

The time-track mode has a couple of useful features - readline & history integration, and prompting and storing a timestamp. It’s not perfect; one of the key things is that the timestamp prompt doesn’t update in real time (although it does store the current time in the text file rather than the potentially out-of-date displayed time). The implementation of the time-track loop is the following:

now=$(date '+%Y/%m/%d %H:%M')
# read history from previous
history -r $HIST_FILE
while read -ep "$now >> " track_input ; do
    now=$(date '+%Y/%m/%d %H:%M')
    if [[ -z $track_input ]] ; then
        # don't store blank lines
        continue
    fi
    # use -- to indicate end to options e.g. if track_input
    # starts with '->' which previously caused errors
    history -s -- "$track_input"
    echo "$now $track_input" >> ${TARGET_PATH}
done
# append current session to history
history -a $HIST_FILE
# ensure bash prompt starts on a new line
echo

I use this every day at work, and it's got to the stage where I want to use it more. I've got plenty of ideas for things to integrate into my implementation, though the real essence of it doesn't need anything clever really.

Monday 24 September 2012

Project Naming in a Google World

I’m a great fan of Python; not only do I think the language itself is clean and readable, the community polite and helpful, and the ecosystem diverse and fascinating, but also the Zen of Python resonates with me.

I think there is significant value in that ‘there should be one - and preferably only one - obvious way to do it’, and that ‘namespaces are one honking great idea’. To me, it is sad that this essence of Python philosophy isn’t applied more widely.

Of course there is an element of tension in the Zen - Namespaces are about nesting, but ‘Flat is better than nested’. Nevertheless, flat within namespaces isn’t the same as not having any namespaces at all.

Namespaces don’t exist in a Google world.

I bet that most project name searches on Google are a single word. ‘jquery’ would get me want I want. ‘requests’ gets me what I want. Even one of my own projects - ‘pylibftdi’ gets me where I want to go. Getting to this point is probably part of choosing a good name. But that’s exactly the problem: how do I choose a good name for my new project? It’s one thing already knowing what project I’m interested in and simply using Google to get me there (sometimes a language name qualifier helps, e.g. ‘python flask’), it’s quite another two problems a) searching for a project to meet a given problem, not knowing what might be available b) searching for a project name I can use for my shiny new thing.

Searchable Project Names

One of the technologies I use the most at work is SSH. I tend to use it mostly in a fairly crude way, via it’s normal client and server programs ssh and sshd with many configuration options, but I have used the paramiko library. Which works well, and has a great name - easily remembered, especially after reading about its etymology on the project page. And very easily searchable. Recently, however, it’s development has slowed. I read in some places that it is now ‘deprecated’, but I’m not sure about that - the github project was last updated 11 days ago as of now… Anyhow, recently it has been forked, and its ‘successor’, has the brilliant name of… wait for it… ‘ssh’. Yes, brilliant. No, actually, it isn’t that helpful. Search for ‘ssh’, and it obviously won’t be there, straightaway, on the first page. Search for ‘python ssh’, and it still won’t be there. I guess it might be in a few months or years once it (presumably) takes off as the ‘one way to do it’, but now? It’s not helpful. Maybe it’s only aimed at people who use the PyPI search engine? And even if / when it is ‘obvious’, it’s still going to be a pain to do web searches for problems relating to use of the package. If I want to know which to use, then ‘paramiko vs ssh’ is of no help. Is the new ssh module ‘preferred’ by the community going forward? Or is it just a random fork by the Fabric guys? Other than the download stats on PyPI, it’s difficult to tell, because searching for info about it is... tricky.

As another example, the pbs package has recently changed its name to sh. Now pbs might not be the bestest name, but changing it to sh causes exactly the same kind of problem as ssh. There can be a real feeling of ‘hijacking’ when something so domain specific is used for a general project name. Using such a name is a clear signal: this is the module you should want to use for this task - you’d would be crazy to try anything else! That may or may not be intended or justified, but when it is a trivial thing for anyone to do, we developers have to be very careful and deliberate. Domain-specific project names, with massively overloaded meanings, only make sense in a very defined namespace: in these cases, the set of Python packages on PyPI.

Except, in a Google world, there aren’t namespaces.

Finding a project name (or rather finding the absence of one)

One of the problems with project naming in a flat unified project namespace (because of course there is one namespace) is project name squatting. For a variety of reasons - good and bad - developers decide that ‘release early, release often’ is a good policy. And one of the first things needed for that first visible release - perhaps the only thing needed - is a project name. So names are snapped up in an eager race. Project names have become the new hot-property. So we have lots of great project ideas, which need and find an awesome project name, make that first release, … and then do nothing. Stagnate. Just like the dot-com crazy days, we have project-name squatting, and permanent project-name ‘under construction’ empty shells… And, like defunct satellites cluttering low-earth orbit, the debris of project names now unused is a danger to every other project, trying to find its own space and path through the knowledge-sphere, avoiding the no-man’s land which has been staked out and left barren, taking juicy spectrum in an interference causing blackout. Soon there will be no more names left and [Sorry, I seem to have got carried away. Ahem.]

So…?

The following are some more thoughts and examples. Most of this is subjective. Hurrah for being able to dump half-finished ideas in a well name-spaced environment!

Over-general names:

  • ‘node’ - really unhelpful.
  • ‘windows’ - key element in GUI programming. WIMP.
  • ‘dropbox’ - to a certain extent.
  • ‘color’ - remember them? Good thing they didn’t take this word away…
  • ‘word’ - a tool for writing words?
  • eliminate a name not just from the project namespace, but increasingly from the word namespace.
  • makes web searching harder

Unpleasant / generally bad names:

  • git
  • gimp
  • My[anything] ;-)
  • Any number of ‘offensive’ or ‘wrong connotation’ names, often leading to name changes, which help no one, except in an ‘any publicity is good publicity’ kind of way:

Duplicate projects with the same name:

Create or recognise our own namespaces:

  • blog articles: author + title
  • PyPI / CPAN etc
  • ‘hungarian notation’ e.g. pyxyz, where the ‘py’ prefix includes some indicator of what namespace it lives in.
  • domain name country code extensions - ‘.io’ etc
  • ‘file extension’ as part of project name: ‘node.js’ etc
  • identification by company or organisation: iOS / iPod / i*, gmail, google maps, etc
  • identification by well-known patterns: xUnit, [j/py]Query etc.

Summary

If I were to produce a new vacuum cleaner and call it ‘Vacuum’, then various people might get upset. We (in software development) don’t really want to have to deal with all the legal & trademark clutter - the fact that we can have an idea, create a project and ‘market’ it all in a weekend is awesome, but requires us to act responsibly. Just because we can launch a new project into the orbital (name)space around us, doesn’t mean we must. Though it is awfully tempting… In addition we need to recognise, use, and educate ourselves and others about the namespaces all around us.

So I guess what I’m really saying, is (to quote Tim Peters)...

Namespaces are one honking great idea - let’s do more of those!

Sunday 10 June 2012

pylibftdi v0.10 released

I’ve recently released pylibftdi v0.10. pylibftdi is a ‘minimal Pythonic interface to libftdi’, and is intended to be (possibly?) the easiest way to get up and running for simple use cases of FTDI’s range of USB to serial and parallel interface chips and modules. v0.10 adds a couple of new features and bug fixes.

For a long time I suffered under the misapprehension that version numbers should follow the rules of decimal numbers, and that by all reasonable accounts v1.0 should have followed 0.9, and since I want(ed) 1.0 to be ‘stable’ (I currently classify it as ‘beta’), I’d reached an impasse. I can’t remember the exact moment, but I had a realisation that I didn’t have to approach 1.0 via smaller and smaller increments from 0.9 (as in Zeno’s race), but that I could go from 0.9 to 0.10. Anyway, I still want to do better documentation (and a few other things) before reaching 1.0.

Changes in v0.10:

  • Running the unit tests is now easier due to some reorganisation - just run python -m unittest discover in the top level directory.

  • Support for the FT232H device - this has a different USB product ID (PID) to the previous devices I’d been testing with and using - mainly FT245BM/RL, FT232R/RL. All those devices have a PID of 0x6001, while the newer FT232H has a PID of 0x6014. I experimented for a while with having (defaulted) extra parameters for specifying the VID and PID of the target device, but this pushed too much complexity up to the user - I really want pylibftdi to be something which can be used with default options and next-to-no set up code for most basic operations. The approach taken is to have two lists (USB_VID_LIST, USB_PID_LIST) and have the device finding code iterate over the cartesian product of these (i.e. a nested loop, but implemented through the wonderful itertools.product). So adding new PIDs in the future is as simple as appending to USB_PID_LIST, and a device can be opened with no parameters to the Device() constructor if it’s the only FTDI device on the USB bus.

  • Resetting the device to serial mode on open. There’s been discussion about implementing this logic in the library on the libftdi mailing list, but doing it in pylibftdi as well doesn’t hurt. This fixes the unexpected condition that if a previous application had used a device in BitBang mode, reopening it just using Device() would leave it in BitBang mode, rather than the expected serial mode (for devices which have support both).

  • Added a ‘buffer_size’ parameter to the Device() constructor (defaulted to zero, which retains previous behaviour) which chunks reads and writes into accesses of that length at most. This avoids the issue that a call of (for example) dev.write(‘hello’ * 100000) over a 9600 serial link would take an incredibly long time, and since it is all running in the library context (via a ctypes call), it wouldn’t be interruptible by Ctrl-C.

  • Removed the deprecated use of Driver() to be a synonym for Device().

  • Update: I've already done two maintenance releases in the hours since originally writing this - v0.10.2 is now current. One of the major changes is that the examples subpackage is now included in the sdist - so python -m pylibftdi.examples.led_flash should work if you have an LED attached to D0 on your device.

The plan for the next release is just more tidy-ups, examples and more documentation, but I might squeeze a few other things in there…

Friday 8 June 2012

My First 3 hours with a Raspberry Pi

My Raspberry Pi arrived a couple of weeks ago, but I've been too busy to play with it til now. And tomorrow I'll be too busy with different things :-)

I'd intended to put Arch Linux on it, since that's what I use on my Pogoplug, and it works really nicely there. But, starting at the downloads page (http://www.raspberrypi.org/downloads) I decided that since the Debian install seemed to have some 'official'ness about it, I'd start there. It pointed to http://elinux.org/RPi_Easy_SD_Card_Setup, which contains a list of 'lazy/easiest/easy/...' and so on approaches to getting a card set up.

A link on that page led to a Mac-only (for now) script which downloads and writes an image to an SD card all in one operation - nothing too difficult to do manually, but I'm not one to ignore easy options. Mostly. http://exaviorn.com/raspiwrite/

I'd bought a Sandisk Extreme 8GB SDHC card - which is on 'the list' by the way - for use with my RPi. I ran the RasPiWrite script firstly with Debian, then Arch Linux. Neither worked. No 'OK' LED, only the red Power LED. Somewhat disappointed. As a side-note, the RasPiWrite script worked better if I reformatted (standard FAT) the card between attempts; otherwise it initially considered selecting my external hard drive, which wasn't great - but it did warn and I was aware, so no worries (for me) there.

I then wondered what the OK LED was supposed to indicate, and read (here: http://www.raspberrypi.org/phpBB3/viewtopic.php?f=28&t=6735) that it should be expected to at least flicker a little on power up - and it wasn't. I had another SDHC card (an old Transcend 4GB SDHC Class 6) and decided to try that. After re-runninge RasPiWrite on it with Debian again, ... the OK light did stuff! It appears to be an SD access light - this wasn't mentioned anywhere I noticed - but it isn't just constantly on when the system is booted, but flickers on activity. So I was sure it was finally booting. I'd read a bunch of things suggesting that as well as dodgy SD cards, flaky PSUs could be a fault, but the two I used (a Blackberry phone charger and an iPad charger) both worked fine in the end.

Sadly however, there was no output on HDMI, butfrom my router's DHCP client list that it was taking a lease. A quick OUI scan showed the Raspberry Pi foundation as the owner of a new MAC in the table :-) I'd foolishly assumed ssh would work out of the box, but nmap showed just port 111 open. Following the instructions here (http://www.youtube.com/watch?v=SmMMKojOE4U) to enable SSH worked great. (Basically 'ssh-keygen; service ssh start; update-rc.d ssh defaults' as root), and I could ssh in! Hurrah!

After reading a few places that sometimes the RCA could work even if HDMI didn't, I found an RCA-SCART adapter and magic - it was actually doing stuff! Finally, after searching and finding http://elinux.org/R-Pi_ConfigurationFile and http://www.raspberrypi.org/phpBB3/viewtopic.php?f=28&t=6762 I got HDMI working by (while logged in over SSH) by creating a /boot/config.txt file (there wasn't an old one) containing the following:

config_hdmi_boost=4
hdmi_force_hotplug=1

And that was it - task accomplished.

Since it's listed in the 'working SD card' list, presumably more recent kernels might work with the bigger / faster card I bought for the purpose of running my RPi; IMO it should be a priority to keep images on the downloads page current - containing latest kernels supporting as wide-a-range of SD cards as possible. I'm sure many have fewer hassles than me, and equally sure many have had many more problems. But for this whole endeavour to really work, it needs to get easier. Is RPi about teaching programming, fun, and 'computing', or about the harsh realities of embedded Linux? Fortunately there is an awesome community which I'm confident will keep pushing things forward - thanks!

Monday 7 May 2012

urlsearch - web searching from the command line

Continuing my pursuit of having a custom vocabulary on my command line, preferably via argv[0] abuse, I've now addressed the subject of web searching. I probably make somewhere between 20 and 50 searches in a typical day, mostly on Google, but Wikipedia comes high up on the list too.

urlsearch is a small script which kicks off a browser search from the command line. The plan is that the task switch associated with switching from the command line (where you usually are, right?) to the browser is eliminated. By complex, spurious and - to-be-frank - non-existent calculations, I estimate that this reduction in friction getting your work done should make you 4.6% more productive, and thus make the world a better place.

Using Python's webbrowser module, it's straightforward to open a webbrowser to a particular page:

>>> import webbrowser
>>> webbrowser.open('http://google.com/search?q=standard+library+pep8')

What urlsearch gives is the equivalent to the above from the following at a Bash prompt:

$ google standard library pep8

It's simple, short, and in it's basic form is just a couple of lines of Python:

#!/usr/bin/env python
import sys, urllib, webbrowser

webbrowser.open('http://google.com/search?q=' +
                urllib.quote_plus(' '.join(sys.argv[1:])))

Make that executable, put it in the path, and you're good-to-go with google [1] searching from the command line. However, as always, complexity is lurking, and desires to have it's way...

The following things are addressed in urlsearch:

Automatic gTLD checking

A range of gTLDs are searched in turn using socket.getaddrinfo(HOSTNAME, 'http'). By default this list starts with the empty gTLD (so local search domains are tried first), then .com, .org, .net, and .co.uk are tried in that order - these being most relevant to my uses. Changing it to default to '.fr' first might be reasonable for French-speakers, for example, but avoiding having to think about this is one more thing not to have to think about. As it were.

Generic search engine support

This is where the wonder of argv[0] fits in :-) Via symlinks to urlsearch, various search engines can be supported. An argv[0] of 'google' will cause a google.com search, while 'wiki' is special-cased to wikipedia. The search query format also needs special-casing for many search engines - the default of /search?q={terms} works for Google, Bing and several other sites.

The following sites are directly supported or special cased:

argv[0] search engine
google Google
bing Bing
wiki Wikipedia
duckduckgo DuckDuckGo
pylib Python standard libraries (direct jump)
jquery jQuery API search (direct jump)

These are managed in the code by a very dull if/elif chain, though something a bit less 'hackish' would probably be wanted to scale to further engines.

Trac support

Trac [2] follows the same search query format as Google, and has a great 'quickjump' feature, where certain search query formats take the user directly to the relevant page. For example, a search for r5678 will go directly to the changeset for revision 5678, and a search for #1234 will go directly to ticket 1234. This ticket search can't be done from a Bash prompt however, as it will be treated as a comment and ignored. This is special cased such that if the search term is an integer, it will be preceded with '#'.

Other tweaks

Output from the browser writing into the command prompt (as happens with Chrome, for example) is redirected to /dev/null.

The Code.

The code is here: http://bitbucket.org/codedstructure/urlsearch

[1]Other search vendors are available
[2]http://trac.edgewall.org

Sunday 29 January 2012

editfile - editing text files made twice as easy

It's been far too long since I wrote anything on this blog, so I'm easing myself back into it with what I've found to be a nice shortcut over the last few months. It uses one of my favourite POSIX tricks - symlinks to executables, together with behaviour based on the original symlink's name - the 'zeroth' argument to the executable.

As someone who identifies fully - and then some - with this xkcd comic: The General Problem, I would really rather not have to type commands which require options. I like aliases, preferably one or two characters long, and I would prefer to write one long word than a short word with an option or two. The mental effort of typing a single word to do a specific action is exactly what I want.

Which leads me to the problem. Text files are great. I am (or was) regularly opening editors, making notes, and saving them somewhere random. The problem is that, like standards, there quickly become too many of them. Which one to use? How to keep track of them? The problem is that the action 'edit my notes file' has to be split into two: a 'verb' (edit), and an 'object' (that particular file). Now you might think I'm irredeemably lazy, but that's twice as many things to remember - or type - as I'd like. I could just add an alias to .bash_aliases, but that's no fun, and while I could have a bunch of them, if I wanted to do anything more complex, I'd be repeating myself too much. Laziness, remember? Got to solve 'The General Problem', and then never have to worry about the specifics ever again :-)

One of my fun projects many moons ago was about adding '--xml' options to ordinary posix commands (xmlcmd - because XML may have serious backing in the enterprise, but needs all the help it can get to make this 'the year of XML on the Linux desktop'), and in it I create symlinks from ~/bin/name-of-posix-command to a Python script which then looks up and runs the original command (using the Python which package), before encoding that command's output into XML to be returned to the user. So basically:

  • Symlinks in a path early in $PATH to a common script
  • Use of argv[0] / $0 in that script to know from which command it was called, and act accordingly.

(And which ls on all my computers still shows $HOME/bin/ls, even though I hardly ever use the --xml option - isn't transparency nice?)

Applying these techniques to the rather simpler - yet more useful - task of editing files, and jumping to the punchline, I have this in ~/bin/editfile:

#!/bin/bash
EDITFILE_DIR=~/Dropbox/editfile
mkdir -p $EDITFILE_DIR  # ensure this exists
TARGET_PATH=$EDITFILE_DIR/$(basename $0).txt

case $1 in
    '-a')
        # append command arguments to file and exit
        shift  # don't include the '-a'
        echo "$*" >> $TARGET_PATH
        ;;
    '-l')
        # list file and exit
        cat $TARGET_PATH
        ;;
    *)
        # Determine editor to use
        if [[ -n "${EDITOR}" ]] ; then
            EDIT=$EDITOR
        elif $(which gedit) ; then
            EDIT="gedit -b"  # default fallback if present
        else
            EDIT="vim"       # fallback if no gedit there
        fi

        # Edit it...
        $EDIT $TARGET_PATH
        ;;
esac

And this:

$ ls -l ~/bin
-rwxr-xr-x  1 ben  staff    714 28 Jan 23:55 editfile
lrwxr-xr-x  1 ben  staff      8 19 Dec 22:13 notes -> editfile
lrwxr-xr-x  1 ben  staff      8 19 Dec 22:50 report -> editfile
lrwxr-xr-x  1 ben  staff      8 19 Dec 22:50 todo -> editfile
lrwxr-xr-x  1 ben  staff      8 19 Dec 22:50 track -> editfile

This has been developed from the much simpler starting point which looked something like this:

#!/bin/bash
gedit ~/$(basename $0)

The result of this is that I can type 'notes' from anywhere on my system, and up will pop my editor with the notes file, which happens to be something on Dropbox, and therefore available on all my computers. I can add as many extra files for different purposes as I like, and they all act in the same way. The files themselves aren't tied into any particular system, and even have helpful '.txt' extensions on the 'actual' files. And since there's a single script behind all of these, they all inherit the 'extras', such as '-l' to list the file, and '-a' to add a line, and I can add extra features and commands, and only have to do it once.

But the main point of all of this is that I've turned a verb + object into a more specific verb, and as long as the first verb is something like 'edit this text file', then I've solved The General Problem too. It might have taken a while longer than 'alias notes="vim ~/Dropbox/editfile/notes.txt"', but that wouldn't have been half as fun. And if you haven't looked at the xkcd comic I linked to earlier, you should now... :-)

I feel the need for a 'today' action, and while I'm at it I should add a todo:

$ (cd ~/bin; ln -s editfile today)
$ todo -a blog post about recently released pylibftdi 0.9