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Iterable can be anything for which items are received one by one, forward only. Built-in Python collections are iterable: [1, 2, 3] # list, iterate over items (1, 2, 3) # tuple {1, 2, 3} # set {1: 2, 3: 4} # dict, iterate over keys Generators return iterables: def foo(): # foo ...

s = {1, 2, 3} # get every element in s for a in s: print a # prints 1, then 2, then 3 # copy into list l1 = list(s) # l1 = [1, 2, 3] # use list comprehension l2 = [a * 2 for a in s if a > 2] # l2 = [6]

def gen(): yield 1 iterable = gen() for a in iterable: print a # What was the first item of iterable? No way to get it now. # Only to get a new iterator gen()

Setting up settings.py from django.utils.translation import ugettext_lazy as _ USE_I18N = True # Enable Internationalization LANGUAGE_CODE = 'en' # Language in which original texts are written LANGUAGES = [ # Available languages ('en', _("English")), ('de', _("Germ...

In order to efficiently handle cycle detection, we consider each node as part of a tree. When adding an edge, we check if its two component nodes are part of distinct trees. Initially, each node makes up a one-node tree. algorithm kruskalMST'(G: a graph) sort G's edges by their value MST ...

The above forest methodology is actually a disjoint-set data structure, which involves three main operations: subalgo makeSet(v: a node): v.parent = v <- make a new tree rooted at v subalgo findSet(v: a node): if v.parent == v: return v return findSet(v.parent...

We can do two things to improve the simple and sub-optimal disjoint-set subalgorithms: Path compression heuristic: findSet does not need to ever handle a tree with height bigger than 2. If it ends up iterating such a tree, it can link the lower nodes directly to the root, optimizing future trav...

Sort the edges by value and add each one to the MST in sorted order, if it doesn't create a cycle. algorithm kruskalMST(G: a graph) sort G's edges by their value MST = an empty graph for each edge e in G: if adding e to MST does not create a cycle: add e to MST ...

var user = Sitecore.Security.Accounts.User.FromName("sitecore/testname", false); using (new Sitecore.Security.Accounts.UserSwitcher(user)) { var item = Sitecore.Context.Database.GetItem("/sitecore/content/home"); }

NSError *e = nil; NSString *jsonString = @"[{\"id\": \"1\", \"name\":\"sam\"}]"; NSData *data = [jsonString dataUsingEncoding:NSUTF8StringEncoding]; NSArray *jsonArray = [NSJSONSerialization JSONObjectWithData: data options: NSJSONReadingMutabl...

Just like in case of the function arguments, template parameters can have their default values. All template parameters with a default value have to be declared at the end of the template parameter list. The basic idea is that the template parameters with default value can be omitted while template ...

Useful if your program is outputting web pages along the way. from http.server import HTTPServer, CGIHTTPRequestHandler import webbrowser import threading def start_server(path, port=8000): '''Start a simple webserver serving path on port''' os.chdir(path) httpd = HTTPServer((''...

Use associated type when there is a one-to-one relationship between the type implementing the trait and the associated type. It is sometimes also known as the output type, since this is an item given to a type when we apply a trait to it. Creation trait GetItems { type First; // ^~~~ d...

Rust's #[path] attribute can be used to specify the path to search for a particular module if it is not in the standard location. This is typically discouraged, however, because it makes the module hierarchy fragile and makes it easy to break the build by moving a file in a completely different dire...

Haxe is available on Windows, Linux, and OS X. It is distributed in two forms: as an installer, providing an optional Neko VM dependency and configuring haxe and haxelib environment variables; as binaries, providing only the Haxe compiler and package manager. Windows Installer and binaries a...

#Post to pagerduty.com notification pagerduty { post = https://events.pagerduty.com/generic/2010-04-15/create_event.json contentType = application/json runOnActions = false body = `{ "service_key": "myservicekey", "incident_key": {{.|jso...

Build constraints are commonly used to separate normal unit tests from integration tests that require external resources, like a database or network access. To do this, add a custom build constraint to the top of the test file: // +build integration package main import ( "testing&...

We can optimize a simple xor function for only architectures that support unaligned reads/writes by creating two files that define the function and prefixing them with a build constraint (for an actual example of the xor code which is out of scope here, see crypto/cipher/xor.go in the standard libra...

Get the Source Package from http://typo3.org/download/ and upload this package to your web server. Put it one level above the document root. For this manual, we will use the .tar.gz file. Use the shell to execute the according commands: /var/www/site/htdocs/$ cd .. /var/www/site/$ wget get.typo3....

The spacing should be even and uniform throughout. Improper indentation can cause an IndentationError or cause the program to do something unexpected. The following example raises an IndentationError: a = 7 if a > 5: print "foo" else: print "bar" print "done&qu...