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Best explanation for languages without null
... that every reference type gets this extra state in its space that is typically undesired. A string variable could be any sequence of characters, or it could be this crazy extra null value that doesn't map into my problem domain. A Triangle object has three Points, which themselves have X and Y va...
How to return value from an asynchronous callback function? [duplicate]
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This is impossible as you cannot return from an asynchronous call inside a synchronous method.
In this case you need to pass a callback to foo that will receive the return value
function foo(address, fn){
geocoder.geocode( { 'address': address}, function(results, status) {
fn(r...
How can I get the current date and time in UTC or GMT in Java?
...TC. It's most accurate to say that Date itself doesn't have a time zone at all - it's just an instant in time, which could be regarded in multiple time zones. But when you create an instance, it doesn't depend on your time zone.
– Jon Skeet
Dec 28 '12 at 12:33
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Can “using” with more than one resource cause a resource leak?
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No.
The compiler will generate a separate finally block for each variable.
The spec (§8.13) says:
When a resource-acquisition takes the form of a
local-variable-declaration, it is possible to acquire multiple
resources of a given type. A using statement of the...
How to achieve function overloading in C?
...sociation list that looks a bit like a switch block. _Generic gets the overall type of the expression and then "switches" on it to select the end result expression in the list for its type:
_Generic(1, float: 2.0,
char *: "2",
int: 2,
default: get_two_object());
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Can I install Python windows packages into virtualenvs?
Virtualenv is great: it lets me keep a number of distinct Python installations so that different projects' dependencies aren't all thrown together into a common pile.
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MySQL, Check if a column exists in a table with SQL
...pecific column, and if not — create it. Otherwise do nothing. This is really an easy procedure in any enterprise-class database, yet MySQL seems to be an exception.
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What is an undefined reference/unresolved external symbol error and how do I fix it?
... token is converted into a token. (2.7). The
resulting tokens are syntactically and semantically analyzed and
translated as a translation unit. [SNIP]
Translated translation units and instantiation units are combined as follows: [SNIP]
All external entity references are resolved. Library components ...
What is the main difference between PATCH and PUT request?
...ied by the Request-
URI. The set of changes is represented in a format called a "patch
document" identified by a media type. If the Request-URI does not
point to an existing resource, the server MAY create a new resource,
depending on the patch document type (whether it can logically modify...
Any way to make a WPF textblock selectable?
How to allow TextBlock 's text to be selectable?
15 Answers
15
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