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What are the differences between Deferred, Promise and Future in JavaScript?
...the differences between Deferreds, Promises and Futures?
Is there a generally approved theory behind all these three?
5 A...
CMake: Print out all accessible variables in a script
I'm wondering if there is a way to print out all accessible variables in CMake. I'm not interested in the CMake variables - as in the --help-variables option. I'm talking about my variables that I defined, or the variables defined by included scripts.
...
C++ static virtual members?
...
No, there's no way to do it, since what would happen when you called Object::GetTypeInformation()? It can't know which derived class version to call since there's no object associated with it.
You'll have to make it a non-static virtual function to work properly; if you also want to be...
PHP and Enumerations
...
Depending upon use case, I would normally use something simple like the following:
abstract class DaysOfWeek
{
const Sunday = 0;
const Monday = 1;
// etc.
}
$today = DaysOfWeek::Sunday;
However, other use cases may require more validation of cons...
Using python's eval() vs. ast.literal_eval()?
...
datamap = eval(raw_input('Provide some data here: ')) means that you actually evaluate the code before you deem it to be unsafe or not. It evaluates the code as soon as the function is called. See also the dangers of eval.
ast.literal_eval raises an exception if the input isn't a valid Python dat...
What are the differences between the different saving methods in Hibernate?
...g of the methods. Mainly these are based on the API though as I don't use all of these in practice.
saveOrUpdate
Calls either save or update depending on some checks. E.g. if no identifier exists, save is called. Otherwise update is called.
save
Persists an entity. Will assign an identifier if...
What is the purpose of AsQueryable()?
...emory data source so that you can more easily test methods that will eventually be used on a non-enumerable based IQueryable.
You can write helper methods for manipulating collections that can apply to either in-memory sequences or external data sources. If you write your help methods to use IQuery...
NodeJS: How to get the server's port?
...eServer();
// Configuration
app.configure(function(){
app.set('views', __dirname + '/views');
app.use(express.bodyDecoder());
app.use(express.methodOverride());
app.use(express.compiler({ src: __dirname + '/public', enable: ['less'] }));
app.use(app.router);
app.use(express.staticProvi...
SparseArray vs HashMap
...pe.
There are some variants for different key/value types, even though not all of them are publicly available.
Benefits are:
Allocation-free
No boxing
Drawbacks:
Generally slower, not indicated for large collections
They won't work in a non-Android project
HashMap can be replaced by the fol...
Stop Excel from automatically converting certain text values to dates
...string literal is the content of the string. Thus the quotation marks magically disappear. You can put =1+2+3 and get the value 6 after CSV import. The formula itself is not destroyed in the import process.
– lokori
Oct 8 '14 at 13:16
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