Tutorial by Examples: lit

Use std::string::substr to split a string. There are two variants of this member function. The first takes a starting position from which the returned substring should begin. The starting position must be valid in the range (0, str.length()]: std::string str = "Hello foo, bar and world!"...

This uses the Dropbox Python SDK to create a shared link for a file and also supplies a requested visibility and expiration in the settings: import datetime import dropbox dbx = dropbox.Dropbox("<ACCESS_TOKEN>") expires = datetime.datetime.now() + datetime.timedelta(days=30...

The Problem The abstract equality and inequality operators (== and !=) convert their operands if the operand types do not match. This type coercion is a common source of confusion about the results of these operators, in particular, these operators aren't always transitive as one would expect. &...

Apple's Reachability class periodically checks the network status and alerts observers to changes. Reachability *internetReachability = [Reachability reachabilityForInternetConnection]; [internetReachability startNotifier];

All the examples in this paragraph print the line !"#$&'()*;<=>? @[\]^`{|}~ A backslash quotes the next character, i.e. the next character is interpreted literally. The one exception is a newline: backslash-newline expands to the empty string. echo \!\"\#\$\&\'\(\)\*\;\...

Array types inherit their equals() (and hashCode()) implementations from java.lang.Object, so equals() will only return true when comparing against the exact same array object. To compare arrays for equality based on their values, use java.util.Arrays.equals, which is overloaded for all array types...

Anonymous type equality is given by the Equals instance method. Two objects are equal if they have the same type and equal values (through a.Prop.Equals(b.Prop)) for every property. var anon = new { Foo = 1, Bar = 2 }; var anon2 = new { Foo = 1, Bar = 2 }; var anon3 = new { Foo = 5, Bar = 10 }; ...

The accessibility frame is used by VoiceOver for hit testing touches, drawing the VoiceOver cursor, and calculating where in the focused element to simulate a tap when the user double-taps the screen. Note that the frame is in screen coordinates! myElement.accessibilityFrame = frameInScreenCoordina...

VoiceOver can navigate many apps on iOS because most UIKit classes implement UIAccessibilityProtocol. Features that don’t represent onscreen elements using UIView, including apps that leverage Core Graphics or Metal to perform drawing, must describe these elements for accessibility. As of iOS 8.0, t...

Stability in sorting means whether a sort algorithm maintains the relative order of the equals keys of the original input in the result output. So a sorting algorithm is said to be stable if two objects with equal keys appear in the same order in sorted output as they appear in the input unsorted a...

The main difference is that double-quoted String literals support string interpolations and the full set of escape sequences. For instance, they can include arbitrary Ruby expressions via interpolation: # Single-quoted strings don't support interpolation puts 'Now is #{Time.now}' # Now is #{Time...

First, some terminology: argument (actual parameter): the actual variable being passed to a function; parameter (formal parameter): the receiving variable that is used in a function. In Python, arguments are passed by assignment (as opposed to other languages, where arguments can be passed by...

String#split splits a String into an Array, based on a delimiter. "alpha,beta".split(",") # => ["alpha", "beta"] An empty String results into an empty Array: "".split(",") # => [] A non-matching delimiter results in an Array...

public class DatabaseHelper extends SQLiteOpenHelper { private static final String DATABASE_NAME = "Example.db"; private static final int DATABASE_VERSION = 3; // For all Primary Keys _id should be used as column name public static final String COLUMN_ID = "_id&q...

NSDictionary *inventory = @{ @"Mercedes-Benz SLK250" : @(13), @"BMW M3 Coupe" : @(self.BMWM3CoupeInventory.count), @"Last Updated" : @"Jul 21, 2016", @"Next Update" : self.nextInventoryUpdateString };

Let's say we have an interface for logging: interface Logger { function log($message); } Now say we have two concrete implementations of the Logger interface: the FileLogger and the ConsoleLogger. class FileLogger implements Logger { public function log($message) { // Append...

Arrays are available in most programming languages, often using square [] or round () brackets to access the elements, e.g. Carray[6] or VBarray(6).

You can split a String on a particular delimiting character or a Regular Expression, you can use the String.split() method that has the following signature: public String[] split(String regex) Note that delimiting character or regular expression gets removed from the resulting String Array. Exa...

split allows to divide a vector or a data.frame into buckets with regards to a factor/group variables. This ventilation into buckets takes the form of a list, that can then be used to apply group-wise computation (for loops or lapply/sapply). First example shows the usage of split on a vector: Con...

A popular form of data analysis is split-apply-combine, in which you split your data into groups, apply some sort of processing on each group, and then combine the results. Let's consider a data analysis where we want to obtain the two cars with the best miles per gallon (mpg) for each cylinder cou...