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A type that conforms to the SequenceType protocol can iterate through it's elements within a closure: collection.forEach { print($0) } The same could also be done with a named parameter: collection.forEach { item in print(item) } *Note: Control flow statements (such as break or continu...

You can create one table from another by adding a SELECT statement at the end of the CREATE TABLE statement: CREATE TABLE stack ( id_user INT, username VARCHAR(30), password VARCHAR(30) ); Create a table in the same database: -- create a table from another table in the same data...

A static class is lazily initialized on member access and lives for the duration of the application domain. void Main() { Console.WriteLine("Static classes are lazily initialized"); Console.WriteLine("The static constructor is only invoked when the class is first accessed&...

Variables of character type or of a derived type with length parameter may have the length parameter either assumed or deferred. The character variable name character(len=len) name is of length len throughout execution. Conversely the length specifier may be either character(len=*) ... ! Ass...

import pandas as pd import numpy as np np.random.seed(123) x = np.random.standard_normal(4) y = range(4) df = pd.DataFrame({'X':x, 'Y':y}) >>> df X Y 0 -1.085631 0 1 0.997345 1 2 0.282978 2 3 -1.506295 3

If you want to catch all routes, then you could use a regular expression as shown: Route::any('{catchall}', 'CatchAllController@handle')->where('catchall', '.*'); Important: If you have other routes and you don't want for the catch-all to interfere, you should put it in the end. For example: ...

A select case construct conditionally executes one block of constructs or statements depending on the value of a scalar expression in a select case statement. This control construct can be considered as a replacement for computed goto. [name:] SELECT CASE (expr) [CASE (case-value [, case-value] .....

To download the entire repository including the full history and all branches, type: git clone <url> The example above will place it in a directory with the same name as the repository name. To download the repository and save it in a specific directory, type: git clone <url> [dire...

You can create a DataFrame from a list of simple tuples, and can even choose the specific elements of the tuples you want to use. Here we will create a DataFrame using all of the data in each tuple except for the last element. import pandas as pd data = [ ('p1', 't1', 1, 2), ('p1', 't2', 3, 4)...

Component code: angular.module('myModule', []).component('myComponent', { bindings: { myValue: '<' }, controller: function(MyService) { this.service = MyService; this.componentMethod = function() { return 2; }; } }); The test: describe('myComponent', f...

By default, all types in TypeScript allow null: function getId(x: Element) { return x.id; } getId(null); // TypeScript does not complain, but this is a runtime error. TypeScript 2.0 adds support for strict null checks. If you set --strictNullChecks when running tsc (or set this flag in you...

val num = 42d Print two decimal places for num using f println(f"$num%2.2f") 42.00 Print num using scientific notation using e println(f"$num%e") 4.200000e+01 Print num in hexadecimal with a println(f"$num%a") 0x1.5p5 Other format strings can be found ...

If you would like to test a line of macro code without needing to run an entire sub, you can type commands directly into the Immediate Window and hit ENTER to run the line. For testing the output of a line, you can precede it with a question mark ? to print directly to the Immediate Window. Altern...

if ([object respondsToSelector:@selector(someOptionalMethodInProtocol:)]) { [object someOptionalMethodInProtocol:argument]; }

Move Blue to the beginning of the array: NSMutableArray *myColors = [NSMutableArray arrayWithObjects: @"Red", @"Green", @"Blue", @"Yellow", nil]; NSUInteger fromIndex = 2; NSUInteger toIndex = 0; id blue = [[[self.array objectAtIndex:fromIndex] retain]...

Every authenticated user has a Firebase uid that's unique across all providers and is returned in the result of every authentication method. A good way to store your user's data is to create a node to keep all the users's data and to protect it using your security rules - Database { "use...

The dynamic keyword is used with dynamically typed objects. Objects declared as dynamic forego compile-time static checks, and are instead evaluated at runtime. using System; using System.Dynamic; dynamic info = new ExpandoObject(); info.Id = 123; info.Another = 456; Console.WriteLine(info...

Evaluates to the second argument if and only if both of the arguments are truthy. Otherwise evaluates to the first falsey argument. x = True y = True z = x and y # z = True x = True y = False z = x and y # z = False x = False y = True z = x and y # z = False x = False y = False z =...

Oracle's CONNECT BY functionality provides many useful and nontrivial features that are not built-in when using SQL standard recursive CTEs. This example replicates these features (with a few additions for sake of completeness), using SQL Server syntax. It is most useful for Oracle developers findin...

Deleting files The unlink function deletes a single file and returns whether the operation was successful. $filename = '/path/to/file.txt'; if (file_exists($filename)) { $success = unlink($filename); if (!$success) { throw new Exception("Cannot delete $filename&qu...