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public double GetPaymentsTotal(string name) { Contract.Ensures(Contract.Result<double>() >= 0); double total = 0.0; foreach (var payment in this._payments) { if (string.Equals(payment.Name, name)) { total += payment.Amount; } } ...

[ContractClass(typeof(ValidationContract))] interface IValidation { string CustomerID{get;set;} string Password{get;set;} } [ContractClassFor(typeof(IValidation))] sealed class ValidationContract:IValidation { string IValidation.CustomerID { [Pure] get ...

A common use-case for iterators is to perform some operation over a collection of numbers. The example below demonstrates how each element within an array of numbers can be individually printed out to the console. This is possible because arrays implement the IEnumerable interface, allowing clients...

Swift let isPushEnabled = UIApplication.sharedApplication().isRegisteredForRemoteNotifications()

The logic of registering for push notification is recommended to be added in AppDelegate.swift as the callback functions (success, failure) will be called their. To register just do the following: let application = UIApplication.sharedApplication() let settings = UIUserNotificationSettings(forType...

Once user clicks on a push notification, the following callback function will be called. You can parse the JSON to get any specific info sent from backend that will helps you in deep linking: Swift func application(application: UIApplication, didReceiveRemoteNotification userInfo: [NSObject : ...

Assume you want to create an extension property that is expensive to compute. Thus you would like to cache the computation, by using the lazy property delegate and refer to current instance (this), but you cannot do it, as explained in the Kotlin issues KT-9686 and KT-13053. However, there is an off...

A stream is closed by sending a closing </stream> tag. After the closing stream tag is sent, no more data should be sent on the stream (even in response to data received from the other party). Before closing the connection, the sending entity should wait for a response </stream> tag to g...

The WHILE loop can be used as an alternative to CURSORS. The following example will print numbers from 0 to 99. DECLARE @i int = 0; WHILE(@i < 100) BEGIN PRINT @i; SET @i = @i+1 END

ToLookup returns a data structure that allows indexing. It is an extension method. It produces an ILookup instance that can be indexed or enumerated using a foreach-loop. The entries are combined into groupings at each key. - dotnetperls string[] array = { "one", "two", &...

dplyr::filter() - Select a subset of rows in a data frame that meet a logical criteria: dplyr::filter(iris,Sepal.Length>7) # Sepal.Length Sepal.Width Petal.Length Petal.Width Species # 1 7.1 3.0 5.9 2.1 virginica # 2 7.6 3.0 ...

Displaying all the logs from the default buffer on the Command Line can be accomplished by: adb logcat This command will show you all the logs from the device's main buffer. Notice that if you use it for the first time, you'll get a lot of information, an enormous stream of data. So you may want...

To install dplyr simply type in the R console. install.packages("dplyr") And then to load dplyr, type library("dplyr") It's also possible to install the latest development version from Github with: if (packageVersion("devtools") < 1.6) { install.packages...

Python Windows The easiest way to install GTK3 for Python is by using PyGObject for Windows. It offers an installer that installs most things you need to develop GTK appilcations. The number of options the PyGObject installer offers can be daunting, but for most GTK projects the only option you h...

git log --stat Example: commit 4ded994d7fc501451fa6e233361887a2365b91d1 Author: Manassés Souza <[email protected]> Date: Mon Jun 6 21:32:30 2016 -0300 MercadoLibre java-sdk dependency mltracking-poc/.gitignore | 1 + mltracking-poc/pom.xml | 14 ++++++++++++-- ...

This example is written with F# in mind but the ideas are applicable in all environments The first rule when optimizing for performance is to not to rely assumption; always Measure and Verify your assumptions. As we are not writing machine code directly it is hard to predict how the compiler an...

This error happens if a unknown object is used. Variables Not compiling: #include <iostream> int main(int argc, char *argv[]) { { int i = 2; } std::cout << i << std::endl; // i is not in the scope of the main function return 0; } Fix: #i...

This linker error happens, if the linker can't find a used symbol. Most of the time, this happens if a used library is not linked against. qmake: LIBS += nameOfLib cmake: TARGET_LINK_LIBRARIES(target nameOfLib) g++ call: g++ -o main main.cpp -Llibrary/dir -lnameOfLib One might also for...

The compiler can't find a file (a source file uses #include "someFile.hpp"). qmake: INCLUDEPATH += dir/Of/File cmake: include_directories(dir/Of/File) g++ call: g++ -o main main.cpp -Idir/Of/File

An interesting but rather unknown usage of Active Patterns in F# is that they can be used to validate and transform function arguments. Consider the classic way to do argument validation: // val f : string option -> string option -> string let f v u = let v = defaultArg v "Hello&quo...