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If you ignore files by using a pattern but have exceptions, prefix an exclamation mark(!) to the exception. For example: *.txt !important.txt The above example instructs Git to ignore all files with the .txt extension except for files named important.txt. If the file is in an ignored folder, y...

Getting the minimum of a sequence (iterable) is equivalent of accessing the first element of a sorted sequence: min([2, 7, 5]) # Output: 2 sorted([2, 7, 5])[0] # Output: 2 The maximum is a bit more complicated, because sorted keeps order and max returns the first encountered value. In case th...

For every infix operator, e.g. + there is a operator-function (operator.add for +): 1 + 1 # Output: 2 from operator import add add(1, 1) # Output: 2 even though the main documentation states that for the arithmetic operators only numerical input is allowed it is possible: from operator impo...

Use array_key_exists() or isset() or !empty(): $map = [ 'foo' => 1, 'bar' => null, 'foobar' => '', ]; array_key_exists('foo', $map); // true isset($map['foo']); // true !empty($map['foo']); // true array_key_exists('bar', $map); // true isset($map['bar']); // false...

A basic join (also called "inner join") queries data from two tables, with their relationship defined in a join clause. The following example will select employees' first names (FName) from the Employees table and the name of the department they work for (Name) from the Departments table:...

The basic closure syntax is { [capture list] (parameters) throws-ness -> return type in body }. Many of these parts can be omitted, so there are several equivalent ways to write simple closures: let addOne = { [] (x: Int) -> Int in return x + 1 } let addOne = { [] (x: Int) -> Int in...

This a Basic example for using the MVVM model in a windows desktop application, using WPF and C#. The example code implements a simple "user info" dialog. The View The XAML <Grid> <Grid.ColumnDefinitions> <ColumnDefinition Width="Auto"/> ...

You can upvote (or downvote, if you want...) examples you created. Although you won't get any reputation for doing so, upvoting your the example will influence the examples' ordering on the page. Any previous contributors to the examples will get reputation. On the other hand, you might consider ...

Overview Checkboxes and radio buttons are written with the HTML tag <input>, and their behavior is defined in the HTML specification. The simplest checkbox or radio button is an <input> element with a type attribute of checkbox or radio, respectively: <input type="checkbox&quo...

The next() built-in is a convenient wrapper which can be used to receive a value from any iterator (including a generator iterator) and to provide a default value in case the iterator is exhausted. def nums(): yield 1 yield 2 yield 3 generator = nums() next(generator, None) # 1 ...

It's possible to create generator iterators using a comprehension-like syntax. generator = (i * 2 for i in range(3)) next(generator) # 0 next(generator) # 2 next(generator) # 4 next(generator) # raises StopIteration If a function doesn't necessarily need to be passed a list, you can sa...

An external CSS stylesheet can be applied to any number of HTML documents by placing a <link> element in each HTML document. The attribute rel of the <link> tag has to be set to "stylesheet", and the href attribute to the relative or absolute path to the stylesheet. While usin...

Jsoup can be be used to easily extract all links from a webpage. In this case, we can use Jsoup to extract only specific links we want, here, ones in a h3 header on a page. We can also get the text of the links. Document doc = Jsoup.connect("http://stackoverflow.com").userAgent("Mozi...

a, b = 2, 3 (a ** b) # = 8 pow(a, b) # = 8 import math math.pow(a, b) # = 8.0 (always float; does not allow complex results) import operator operator.pow(a, b) # = 8 Another difference between the built-in pow and math.pow is that the built-in po...

C99 The header <stdint.h> provides several fixed-width integer type definitions. These types are optional and only provided if the platform has an integer type of the corresponding width, and if the corresponding signed type has a two's complement representation of negative values. See the r...

@media screen and (min-width: 720px) { body { background-color: skyblue; } } The above media query specifies two conditions: The page must be viewed on a normal screen (not a printed page, projector, etc). The width of the user's view port must be at least 720 pixels. I...

You can use the label's textColor property to apply a text color to the entire text of the label. Swift label.textColor = UIColor.redColor() label.textColor = UIColor(red: 64.0/255.0, green: 88.0/255.0, blue: 41.0/225.0, alpha: 1) Swift 3 label.textColor = UIColor.red label.textColor = UICol...

Swift label.textAlignment = NSTextAlignment.left //or the shorter label.textAlignment = .left Any value in the NSTextAlignment enum is valid: .left, .center, .right, .justified, .natural Objective-C label.textAlignment = NSTextAlignmentLeft; Any value in the NSTextAlignment enum is vali...

Jsoup can be used to extract links and email address from a webpage, thus "Web email address collector bot" First, this code uses a Regular expression to extract the email addresses, and then uses methods provided by Jsoup to extract the URLs of links on the page. public class JSoupTest {...

This example uses the Cars Table from the Example Databases. UPDATE Cars SET TotalCost = TotalCost + 100 WHERE Id = 3 or Id = 4 Update operations can include current values in the updated row. In this simple example the TotalCost is incremented by 100 for two rows: The TotalCost of Car #3 i...