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Weird PHP error: 'Can't use function return value in write context'
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You mean
if (isset($_POST['sms_code']) == TRUE ) {
though incidentally you really mean
if (isset($_POST['sms_code'])) {
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How to use performSelector:withObject:afterDelay: with primitive types in Cocoa?
The NSObject method performSelector:withObject:afterDelay: allows me to invoke a method on the object with an object argument after a certain time. It cannot be used for methods with a non-object argument (e.g. ints, floats, structs, non-object pointers, etc.).
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Backwards migration with Django South
Ok, so this seems like a really silly thing to ask, and I'm sure I'm missing something somewhere.
3 Answers
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Most efficient method to groupby on an array of objects
...g callback functions to return a sorting criteria
– y_nk
Jul 6 '16 at 16:50
118
Here is one that ...
Mixin vs inheritance
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A mixin is typically used with multiple inheritance. So, in that sense, there's "no difference".
The detail is that a mixin is rarely useful as a standalone object.
For example, say you have a mixin named "ColorAndDimension", which adds a co...
What is TypeScript and why would I use it in place of JavaScript? [closed]
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I originally wrote this answer when TypeScript was still
hot-off-the-presses. Five years later, this is an OK overview, but look
at Lodewijk's answer below for more depth
1000ft view...
TypeScript is a superset of JavaScript ...
How can I initialize base class member variables in derived class constructor?
...ince it would destroy encapsulation. Instead, create a constructor in A to allow B (or any subclass of A) to initialize them:
class A
{
protected:
A(int a, int b) : a(a), b(b) {} // Accessible to derived classes
// Change "protected" to "public" to allow others to instantiate A.
private:
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Is it safe to parse a /proc/ file?
.../proc/mounts was a consistent snapshot.
For example:
/proc/uptime is totally atomic, as someone mentioned in another answer -- but only since Linux 2.6.30, which is less than two years old. So even this tiny, trivial file was subject to a race condition until then, and still is in most enterpris...
Max or Default?
...wiggering the spacklerorke, and riding the flying unicorn to Neverland are all meaningless, impossible, undefined.
Now, what is it that you actually want to do?
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Mongodb Explain for Aggregation framework
...ther manipulation will be in-memory (possibly using temporary files if the allowDiskUse option is set).
Optimizing pipelines
In general, you can optimize aggregation pipelines by:
Starting a pipeline with a $match stage to restrict processing to relevant documents.
Ensuring the initial $match / ...