Tutorial by Examples: le

(defvar *ht* (make-hash-table)) (loop for (sym num) on '(one 1 two 2 three 3 four 4 five 5 six 6 seven 7 eight 8 nine 9 ten 10) by #'cddr do (setf (gethash sym *ht*) num)) (loop for k being each hash-key of *ht* do (print k)) ; iterate over the keys (loop for k ...

Simple LOOP form without special keywords: (loop forms...) To break out of the loop we can use (return <return value>) ` Some examples: (loop (format t "Hello~%")) ; prints "Hello" forever (loop (print (eval (read)))) ; your very own REPL (loop (let ((r (read))) ...

This example assumes you have already installed Java and Gradle. Use the following project structure: src/ main/ java/ com/ example/ Application.java build.gradle build.gradle is your build script for Gradle build system with the following content: buildscri...

You should implement SFSafariViewControllerDelegate so that your class is notified when the user hits the Done button on the SafariViewController and you can dismiss it as well. First declare your class to implement the protocol. class MyClass: SFSafariViewControllerDelegate { } Implement th...

Don't forget to import the necessary framework first. import SafariServices //Objective-C @import SafariServices; Instantiate a SafariViewController instance. let safariVC = SFSafariViewController(URL: URL(string: "your_url")!) //Objective-C @import SafariServices; NSURL *URL = [...

Run the command below in a shell after installing Ruby. This shows how you can execute simple Ruby programs without creating a Ruby file: ruby -e 'puts "Hello World"' You can also feed a Ruby program to the interpreter's standard input. One way to do that is to use a here document in...

A factory decreases coupling between code that needs to create objects from object creation code. Object creation is not made explicitly by calling a class constructor but by calling some function that creates the object on behalf the caller. A simple Java example is the following one: interface Ca...

docopt turns command-line argument parsing on its head. Instead of parsing the arguments, you just write the usage string for your program, and docopt parses the usage string and uses it to extract the command line arguments. """ Usage: script_name.py [-a] [-b] <path> ...

unique drops duplicates so that each element in the result is unique (only appears once): x = c(2, 1, 1, 2, 1) unique(x) # 2 1 Values are returned in the order they first appeared. duplicated tags each duplicated element: duplicated(x) # FALSE FALSE TRUE TRUE TRUE anyDuplicated(x) >...

Imagine you have the following HTML: <div> <label>Name:</label> John Smith </div> And you need to locate the text "John Smith" after the label element. In this case, you can locate the label element by text and then use .next_sibling property: from ...

BeautifulSoup has a limited support for CSS selectors, but covers most commonly used ones. Use select() method to find multiple elements and select_one() to find a single element. Basic example: from bs4 import BeautifulSoup data = """ <ul> <li class="item&quo...

Have a table NameAgeCityBob10ParisMat20BerlinMary24Prague select Name from table where Age>10 AND City='Prague' Gives NameMary select Name from table where Age=10 OR City='Prague' Gives NameBobMary

Light Table is a good editor to learn, experiment and run Clojure projects. You can also run lein/boot projects by opening project.clj file. It will load all project dependencies. It supports inline evalution, plugins and much more, so there's no need to add print statements and check the output i...

All built-in Clojure collections are immutable and heterogeneous, have literal syntax, and support the conj, count, and seq functions. conj returns a new collection that is equivalent to an existing collection with an item "added", in either "constant" or logarithmic time. Wha...

For if you have to fine-tune what is published. import { Mongo } from 'meteor/mongo'; import { Meteor } from 'meteor/meteor'; import { Random } from 'meteor/random'; if (Meteor.isClient) { // established this collection on the client only. // a name is required (first parameter) and this...

You can commit changes made to specific files and skip staging them using git add: git commit file1.c file2.h Or you can first stage the files: git add file1.c file2.h and commit them later: git commit

In Angular $scope is the glue between the Controller and the View that helps with all of our data binding needs. Controller As is another way of binding controller and view and is mostly recommended to use. Basically these are the two controller constructs in Angular (i.e $scope and Controller As). ...

Lambda expressions can be used to handle events, which is useful when: The handler is short. The handler never needs to be unsubscribed. A good situation in which a lambda event handler might be used is given below: smtpClient.SendCompleted += (sender, args) => Console.WriteLine("Ema...

public interface IShape { decimal Area(); } public struct Rectangle : IShape { public decimal Length { get; set; } public decimal Width { get; set; } public decimal Area() { return Length * Width; } }

Django default project layout creates a single settings.py. This is often useful to split it like this: myprojectroot/ myproject/ __init__.py settings/ __init__.py base.py dev.py prod.py tests.py This enables...