I’ve just spent some time learning about the difference between scala’s functions and methods. It’s a surprisingly complicated topic, so I’ll defer to the smart folks on stack overflow for the explanation itself:

Difference between method and function in Scala

Here are some interesting points / examples I took from that topic:

So let’s say you have a java method:

public Object getSomething(String key) { ... }

This returns an Object, or null. Ideally it would have a generic type so that it at least returned the type you expect (like String), rather than Object, but that’s java for you. What’s a scala chap to do with such an ugly method?

val obj = getSomething("key")
val maybeObj = obj match {
	case s:String => Some(s)
	case _ => None
}
val actualObj = maybeObj.getOrElse("")

Not very nice, is it? We should abstract this (unfortunately) common pattern!

I’ve been using xmonad (with a slightly modified bluetile setup) for about a year now, and it’s been pretty great. But I still feel locked in to its grid sometimes, and miss the direct manipulation that a “normal” window manager (like metacity) provides - specifically allowing quick movement and resizing by using alt + mouse dragging. Bluetile has the option of floating windows, but actually moving or resizing them is so cumbersome that it’s not really worth it. I also sometimes wish that my windows could overlap, so that (while still tiled) a window can extend beyond the bounds of its tile if I want it to.

I also am a sucker for shiny things, and xmonad is far from a shiny thing (in terms of graphics). I tried out gnome-shell yesterday, and while buggy, it is exceedingly shiny. And considering that gnome-shell will not allow alternate window managers (that was a surprise to me), I have put some thought into what my ideal window manager would look like.

I’m keen to try and implement this somewhere. It’s unlikely to be xmonad, as I want builtin compositing support (and haskell is a great language, but I can barely figure out how to configure xmonad, let alone extend it). So I’m wondering if the following can be done as a plugin to either gnome-shell or mutter. Hopefully gnome-shell, as I can stomach javascript hacking a lot easier than compiling C extensions.

Also, if people know of an existing project (with compositing!) that has these sorts of features, I’d be interested to know - I don’t want to have to reinvent the wheel, but it seems like most tiling window managers are too rigid and keyboard-based for me, while most “grid” extensions to floating window managers are too manual.

So, here’s the plan:

All of these lines, in ruby, should fail. All of them instead return nil:

@nonexistant_var
{}[:nonexistant_key]
[].first
{}.shift

All of these were encountered by myself in the course of yesterday’s programming. None of them in a good way. And the last two were in published libraries, not even code under development.

All of these, of course, raise errors in python. I refer you to lines 10 and 11 of the zen of python:

Errors should never pass silently.

Unless explicitly silenced

(an Option or Maybe type would be acceptable also, but that’s pretty uncommon to find in a dynamic language)

Also inviting my fury: every single language, tool or function, ever, that makes you check the return code of a system (shell) command to see whether it was nonzero.

…three days after this post, pea, the tiniest BDD framework is born.

I hereby declare to be monocle. To see why, check out the second example.