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Using smart pointers for class members
I'm having trouble understanding the usage of smart pointers as class members in C++11. I have read a lot about smart pointers and I think I do understand how unique_ptr and shared_ptr / weak_ptr work in general. What I don't understand is the real usage. It seems like everybody recommends using...
Is there a difference between YES/NO,TRUE/FALSE and true/false in objective-c?
Simple question really; is there a difference between these values (and is there a difference between BOOL and bool)? A co-worker mentioned that they evaluate to different things in Objective-C, but when I looked at the typedefs in their respective .h files, YES/TRUE/true were all defined as 1 an...
java.net.ConnectException: localhost/127.0.0.1:8080 - Connection refused
...the emulator.
If you are referring your localhost on your system from the Android emulator then you have to use http://10.0.2.2:8080/ Because Android emulator runs in a Virtual Machine therefore here 127.0.0.1 or localhost will be emulator's own loopback address.
Refer: Emulator Networking
...
In AngularJS, what's the difference between ng-pristine and ng-dirty?
What are the differences between ng-pristine and ng-dirty ? It seems you can have both to be true :
5 Answers
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AngularJS : How to watch service variables?
... always use the good old observer pattern if you want to avoid the tyranny and overhead of $watch.
In the service:
factory('aService', function() {
var observerCallbacks = [];
//register an observer
this.registerObserverCallback = function(callback){
observerCallbacks.push(callback);
...
When to throw an exception?
...e 1: say I have a function which is supposed to examine an arbitrary class and return true if that class inherits from List<>. This function asks the question, "Is this object a descendant of List?" This function should never throw an exception, because there are no gray areas in its operation...
git add, commit and push commands in one?
Is there any way to use these three commands in one?
32 Answers
32
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Sending a mail from a linux shell script
I want to send an email from a Linux Shell script. What is the standard command to do this and do I need to set up any special server names?
...
Split a String into an array in Swift?
... that String no longer adopts the SequenceType or CollectionType protocols and you must instead use the .characters property to access a CharacterView type representation of a String instance. (Note: CharacterView does adopt SequenceType and CollectionType protocols).
let fullName = "First Last"
le...
MySQL: Large VARCHAR vs. TEXT?
... in MySQL which records messages between users. Apart from the typical ids and message types (all integer types) I need to save the actual message text as either VARCHAR or TEXT. I'm setting a front-end limit of 3000 characters which means the messages would never be inserted into the db as longer t...