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How to get the directory of the currently running file?
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It actually works even if os.Args[0] does not contain the abs path. The reason the playground result is not what you expected is because it is inside a sandbox.
– Gustavo Niemeyer
Jul 21 '15 at...
How does '20 seconds' work in Scala?
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There are a few things going on.
First, Scala allows dots and parens to be omitted from many method calls, so 20 seconds is equivalent to 20.seconds()*.
Second, an "implicit conversion" is applied. Since 20 is an Int and Int has no seconds method, the compiler searches ...
What's the difference between “Write-Host”, “Write-Output”, or “[console]::WriteLine”?
... but not necessarily want to display it on screen. The pipeline will eventually write it to out-default if nothing else uses it first.
Write-Host should be used when you want to do the opposite.
[console]::WriteLine is essentially what Write-Host is doing behind the scenes.
Run this demonstratio...
Delete all documents from index/type without deleting type
I know one can delete all documents from a certain type via deleteByQuery.
15 Answers
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How do I sort an array of hashes by a value in the hash?
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Actually, Array#sort_by! is new in Ruby 1.9.2. Available today to all Ruby version by requiring my backports gem too :-)
– Marc-André Lafortune
Jul 1 '10 at 4:19
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dispatch_after - GCD in Swift?
...patch_block_t?)
dispatch_time_t is a UInt64. The dispatch_queue_t is actually type aliased to an NSObject, but you should just use your familiar GCD methods to get queues. The block is a Swift closure. Specifically, dispatch_block_t is defined as () -> Void, which is equivalent to () -> ().
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Separating class code into a header and cpp file
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So this means that all files that include your header file will "see" the private members. If for example you want to publish a lib and its header, you have to show the private members of the class?
– Gauthier
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How to query MongoDB with “like”?
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Actually, it depends. If the query doesn't use an index, and must do a table scan, then it can certainly be expensive. If you're doing a 'starts with' regex query, then that can use an index. Best to run an explain() to see what'...
Iteration over std::vector: unsigned vs signed index variable
...et away with only a conversion in the forward iterating case, it could actually go wrong all the way in the backward iterating case when using std::size_t, in case std::size_t is wider than what is the typedef of size_type):
Using std::vector
Using iterators
for(std::vector<T>::iterator i...
Why do we need C Unions?
...le types together:
enum Type { INTS, FLOATS, DOUBLE };
struct S
{
Type s_type;
union
{
int s_ints[2];
float s_floats[2];
double s_double;
};
};
void do_something(struct S *s)
{
switch(s->s_type)
{
case INTS: // do something with s->s_ints
break;
case F...