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While catching the Throwable, Exception, Error and RuntimeException exceptions is bad, throwing them is even worse. The basic problem is that when your application needs to handle exceptions, the presence of the top level exceptions make it hard to discriminate between different error conditions. ...

adb shell am start -n com.android.settings/.DevelopmentSettings Will navigate your device/emulator to the Developer Options section.

First define an ExitActivity in the AndroidManifest.xml <activity android:name="com.your_example_app.activities.ExitActivity" android:autoRemoveFromRecents="true" android:theme="@android:style/Theme.NoDisplay" /> Afterwards the ExitA...

Detailed instructions on getting azure-service-fabric set up or installed.

Rather than passing a static string as a predicate's criteria. It is possible to substitute values by using format specifiers. There are five format specifiers: %K is a var arg substitution for a key path. %@ is a var arg substitution for an object value-often a string, number, date, or an array...

When we are working on a framework, if the constraints are not too complex, we'd better use Interface Builder or NSLayoutConstraint in code to make it smaller enough, instead of import Masonry or SnapKit. for example: Objective-C // 1. create views UIView *blueView = [[UIView alloc...

Swift classes supports having multiple ways of being initialized. Following Apple's specs this 3 rules must be respected: A designated initializer must call a designated initializer from its immediate superclass. A convenience initializer must call another initializer from the same class. A ...

std::function type erases down to a few operations. One of the things it requires is that the stored value be copyable. This causes problems in a few contexts, like lambdas storing unique ptrs. If you are using the std::function in a context where copying doesn't matter, like a thread pool where ...

To determine the version of Azure PowerShell that you have installed, run the following: Get-Module -ListAvailable -Name Azure -Refresh This command returns the installed version even when you haven't loaded the Azure PowerShell module in your current PowerShell session.

To normalize the database in the second form, there must not be any partial dependency of any column on primary key. Let's consider the following example: idnamedobsubject1Mark1-1-1981Physics2Jack2-2-1982Math2Jack2-2-1982Biology3John3-3-1983Math This table is considered to have a composite primar...

For more advanced regex operations it's best to use CL_ABAP_REGEX and its related classes. DATA: lv_test TYPE string, lo_regex TYPE REF TO cl_abap_regex. lv_test = 'The quick brown fox'. CREATE OBJECT lo_regex EXPORTING pattern = 'q(...)\w'. DATA(lo_matcher) = lo_regex->cr...

class User { String name int age } def users = [ new User(name: "Bob", age: 20), new User(name: "Tom", age: 50), new User(name: "Bill", age: 45) ] def null_value = users.find { it.age > 100 } // no over-100 found. Null null_value?.name?....

for numbers, a zero value evaluates to false, non zero to true int i = 0 ... if (i) print "some ${i}" else print "nothing" will print "nothing"

a string (including GStrings) evaluates to true if not null and not empty, false if null or empty def s = '' ... if (s) println 's is not empty' else println 's is empty' will print: 's is empty'

Collections and Maps evaluates to true if not null and not empty and false if null or empty /* an empty map example*/ def userInfo = [:] if (!userInfo) userInfo << ['user': 'Groot', 'species' : 'unknown' ] will add user: 'Groot' , species : 'unknown' as default userInfo since the u...

a null object reference evaluates to false, a non null reference to true, but for for strings, collections, iterators and enumerations it also takes into account the size. def m = null if (!m) println "empty" else println "${m}" will print "empty" de...

Sometimes it may be useful to have a specific asBoolean definition in your own program for some kind of objects. /** an oversimplified robot controller */ class RunController { def complexCondition int position = 0 def asBoolean() { return complexCondition(this...

Not all type erasure involves virtual inheritance, allocations, placement new, or even function pointers. What makes type erasure type erasure is that it describes a (set of) behavior(s), and takes any type that supports that behavior and wraps it up. All information that isn't in that set of beha...

Install Iron Router From the terminal: meteor add iron:router Basic configuration Router.configure({ //Any template in your routes will render to the {{> yield}} you put inside your layout template layoutTemplate: 'layout', loadingTemplate: 'loading' }); Render without d...

Geospatial collections generally involve storing GeoJSON in the Mongo database, streaming that data to the client, accessing the browser's window.navigator.geolocation, loading up a Map API, converting GeoJSON to LatLngs, and plotting on the map. Preferably all in realtime. Here are a list of reso...