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Fixnum#to_s takes an optional base argument and represents the given number in that base: 2.to_s(2) # => "10" 3.to_s(2) # => "11" 3.to_s(3) # => "10" 10.to_s(16) # => "a" If no argument is provided, then it represents the number in bas...

The Arbitrary class is for types that can be randomly generated by QuickCheck. The minimal implementation of Arbitrary is the arbitrary method, which runs in the Gen monad to produce a random value. Here is an instance of Arbitrary for the following datatype of non-empty lists. import Test.QuickC...

% Define serial port with a baud rate of 115200 rate = 115200; if ispc s = serial('COM1', 'BaudRate',rate); elseif ismac % Note that on OSX the serial device is uniquely enumerated. You will % have to look at /dev/tty.* to discover the exact signature of your % serial device ...

It is common for memory performance to compress multiple values into a single primitive value. This may be useful to pass various information into a single variable. For example, one can pack 3 bytes - such as color code in RGB - into an single int. Packing the values // Raw bytes as input byte...

The SQL 2008 standard defines the FETCH FIRST clause to limit the number of records returned. SELECT Id, ProductName, UnitPrice, Package FROM Product ORDER BY UnitPrice DESC FETCH FIRST 10 ROWS ONLY This standard is only supported in recent versions of some RDMSs. Vendor-specific non-stand...

The for clause of a list comprehension can specify more than one variable: [x + y for x, y in [(1, 2), (3, 4), (5, 6)]] # Out: [3, 7, 11] [x + y for x, y in zip([1, 3, 5], [2, 4, 6])] # Out: [3, 7, 11] This is just like regular for loops: for x, y in [(1,2), (3,4), (5,6)]: print(x+y) ...

Pojo Model public class Model { private String firstName; private String lastName; private int age; /* Getters and setters not shown for brevity */ } Example: String to Object Model outputObject = objectMapper.readValue( "{\"firstName\":\"J...

To retrieve the result of a procedure call (e.g. Function or Property Get procedures), put the call on the right-hand side of an assignment: result = ProcedureName result = ProcedureName(argument1, argument2) Parentheses must be present if there are parameters. If the procedure has no parameter...

Parentheses are used to enclose the arguments of function calls. Using them for procedure calls can cause unexpected problems. Because they can introduce bugs, both at run-time by passing a possibly unintended value to the procedure, and at compile-time by simply being invalid syntax. Run-time Re...

The Objective-C runtime allows you to change the implementation of a method at runtime. This is called method swizzling and is often used to exchange the implementations of two methods. For example, if the methods foo and bar are exchanged, sending the message foo will now execute the implementation...

HTML5 data-* attributes provide a convenient way to store data in HTML elements. The stored data can be read or modified using JavaScript <div data-submitted="yes" class="user_profile"> … some content … </div> Data attribute structure is data-*, i.e. the n...

You can add external SVG files using the background-image property, just as you would do with any other image. HTML: <div class="attention"></div> CSS: .attention { background-image: url(attention.svg); background-size: 100% 100%; width: 50px; height: ...

To search if a String contains a substring, do the following: NSString *myString = @"This is for checking substrings"; NSString *subString = @"checking"; BOOL doesContainSubstring = [myString containsString:subString]; // YES If targeting iOS 7 or OS X 10.9 (or earlier)...

Procedures do something. Name them after what they're doing, using a verb. If accurately naming a procedure is not possible, likely the procedure is doing too many things and needs to be broken down into smaller, more specialized procedures. Some common VBA naming conventions go thus: For all Pr...

Unlike classes, structures cannot inherit: class MyView: NSView { } // works struct MyInt: Int { } // error: inheritance from non-protocol type 'Int' Structures, however, can adopt protocols: struct Vector: Hashable { ... } // works

You can use the Enumerable class alongside Linq queries to convert for loops into Linq one liners. Select Example Opposed to doing this: var asciiCharacters = new List<char>(); for (var x = 0; x < 256; x++) { asciiCharacters.Add((char)x); } You can do this: var asciiCharacter...

When you need to remove a specific value from an array, you can use the following one-liner to create a copy array without the given value: array.filter(function(val) { return val !== to_remove; }); Or if you want to change the array itself without creating a copy (for example if you write a fun...

Composer tracks which versions of packages you have installed in a file called composer.lock, which is intended to be committed to version control, so that when the project is cloned in the future, simply running composer install will download and install all the project's dependencies. Composer de...

The operator for an "exclusive or" (for short XOR) is: ^ This operator returns true when one, but only one, of the supplied bools are true. true ^ false // Returns true false ^ true // Returns true false ^ false // Returns false true ^ true // Returns false

It's possible to treat multiple, distinct values the same way, using |: enum Colour { Red, Green, Blue, Cyan, Magenta, Yellow, Black } enum ColourModel { RGB, CMYK } // let's take an example colour let colour = Colour::Red; let model = match ...