The standard answer is to use packages — see the Writing R Extensions manual as well as different tutorials on the web. It gives you a quasi-automatic way to organize your code by topic strongly encourages you to write a help file, making you think about the interface a lot of sanity checks via R … Read more
For Gems I have seen many times that you define exceptions in this way: gem_dir/lib/gem_name/exceptions.rb and defined as: module GemName class AuthenticationError < StandardError; end class InvalidUsername < AuthenticationError; end end an example of this would be something like this in httparty For Ruby on Rails Put them in your lib/ folder under a file … Read more
Some conventions list all the public methods first, and then all the private ones – that means it’s easy to separate the API from the implementation, even when there’s no interface involved, if you see what I mean. Another idea is to group related methods together – this makes it easier to spot seams where … Read more
You can add elements of a list to a set like this: >>> foo = set(range(0, 4)) >>> foo set([0, 1, 2, 3]) >>> foo.update(range(2, 6)) >>> foo set([0, 1, 2, 3, 4, 5])
if let and guard let serve similar, but distinct purposes. The “else” case of guard must exit the current scope. Generally that means it must call return or abort the program. guard is used to provide early return without requiring nesting of the rest of the function. if let nests its scope, and does not … Read more
You can use Collections.list() to convert an Enumeration to a List in one line: List<T> list = Collections.list(enumeration); There’s no similar method to get a Set, however you can still do it one line: Set<T> set = new HashSet<T>(Collections.list(enumeration));
__str__() is the old method — it returns bytes. __unicode__() is the new, preferred method — it returns characters. The names are a bit confusing, but in 2.x we’re stuck with them for compatibility reasons. Generally, you should put all your string formatting in __unicode__(), and create a stub __str__() method: def __str__(self): return unicode(self).encode(‘utf-8’) … Read more
The trunk is the main line of development in a SVN repository. A branch is a side-line of development created to make larger, experimental or disrupting work without annoying users of the trunk version. Also, branches can be used to create development lines for multiple versions of the same product, like having a place to … Read more
Python evaluates expressions from left to right. Notice that while evaluating an assignment, the right-hand side is evaluated before the left-hand side. Python docs: Evaluation order That means the following for the expression a,b = b,a : The right-hand side b,a is evaluated, that is to say, a tuple of two elements is created in … Read more
The preference for present-tense, imperative-style commit messages comes from Git itself. From Documentation/SubmittingPatches in the Git repo: Describe your changes in imperative mood, e.g. “make xyzzy do frotz” instead of “[This patch] makes xyzzy do frotz” or “[I] changed xyzzy to do frotz”, as if you are giving orders to the codebase to change its … Read more