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User-defined functionals Users can create their own functionals to varying degrees of complexity. The following examples are from Functionals by Hadley Wickham: randomise <- function(f) f(runif(1e3)) lapply2 <- function(x, f, ...) { out <- vector("list", length(x...

Nesting is probably most often used to create more specific selectors, but it can also be used simply for code organization. Using the @at-root directive, you can ‘jump out’ of where you nest it in your Sass, bringing you back at the top level. Doing this allows you to keep styles grouped without cr...

Using SVG stroke makes it easier to create a Vector drawable with unified stroke length, as per Material Design guidelines: Consistent stroke weights are key to unifying the overall system icon family. Maintain a 2dp width for all stroke instances, including curves, angles, and both interior and ...

The number that follows the associativity information describes in what order the operators are applied. It must always be between 0 and 9 inclusive. This is commonly referred to as how tightly the operator binds. For example, consider the following fixity declarations (in base) infixl 6 + infixl ...

The following will prompt a user for input, and then store that input as a string (text) in a variable. The variable is then used to give a message to the user. #!/usr/bin/env bash echo "Who are you?" read name echo "Hello, $name." The command read here reads one line of ...

In same cases different models could have same fields and same procedures in the product life cycle. To handle these similarities without having code repetition inheritance could be used. Instead of inheriting a whole class, mixin design pattern offers us to inherit (or some says include) some met...

In Sinatra, routing is how your app responds to requests, by the path of the request (e.g. /welcome) and by the HTTP verb used (e.g. GET or POST). The way a request is written is as follows: <http-verb> <path> do <code block to execute when this route is requested> end He...

When matching the path of a route, you can do it explicitly, matching only one path, like so: get "/hello" do return "Hello!" end You can also use a regular expression to match complex routes. Any route which matches the regular expression will run that code block. If m...

To print a test field (TestField) from a test feature class (TestFC) in a test file geodatabase (Test.gdb) located in a temporary folder (C:\Temp): with arcpy.da.SearchCursor(r"C:\Temp\Test.gdb\TestFC",["TestField"]) as cursor: for row in cursor: print row[0]

class Animal { abstract int maxSize(); // must be implemented by sub-class final float maxSizeInMeters() // can't be overridden by base class { return maxSize() / 100.0; } } class Lion: Animal { override int maxSize() { return 350; } } void main() { ...

class Lion { private double weight; // only accessible with-in class this(double weight) { this.weight = weight; } double weightInPounds() const @property // const guarantees no modifications // @property functions are treated as fields { ret...

void main() { import std.stdio : writeln; int[] arr = [1, 3, 4, 5]; foreach (i, el; arr) { if (i == 0) continue; // continue with the next iteration arr[i] *= 2; if (i == 2) break; // stop the loop iteration } writel...

If an arithmetic operation that yields a floating point type produces a value that is not in the range of representable values of the result type, the behavior is undefined according to the C++ standard, but may be defined by other standards the machine might conform to, such as IEEE 754. float x =...

When either a signed or unsigned integer is converted to a signed integer type, and its value is not representable in the destination type, the value produced is implementation-defined. Example: // Suppose that on this implementation, the range of signed char is -128 to +127 and // the range of un...

Sometimes in a development or testing environment, the SSL certificate chain might not have been fully established (yet). To continue developing and testing, you can turn off SSL verification programmatically by installing an "all-trusting" trust manager: try { // Create a trust mana...

Config values can be set in three ways: Via private static variables on any class within a SilverStripe project Via yaml config files (stored in module-folder/_config/[file].yml) Via PHP at run time (Config::inst()->update('Director', 'environment_type', 'dev') Generally it's best to se...

Emacs uses the terms point, mark, and region to provide more precision about the selected text and position of the cursor. By understanding these terms, it'll help you understand and use other operations and functions. The point is the place in a buffer where editing (i.e. insertion) is currently t...

Killing and yanking more or less correspond to what is usually called "cutting" and "pasting". Killing killing means deleting text, and copying it to the kill-ring (which could be seen as a sort of "clipboard" in the "cut & paste" terminology). The kill ...

Download Use Firebird site to download the correct "server package" for your system. First, select the version of Firebird that you would like to install. Next, select the appropriated installer for your system. Example, for almost any version of Windows 32 bits, you would select under ...

The Scala Collections framework, according to its authors, is designed to be easy to use, concise, safe, fast, and universal. The framework is made up of Scala traits that are designed to be building blocks for creating collections. For more information on these building blocks, read the official S...