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Rails: around_* callbacks
...classes/ActiveRecord/Callbacks.html , but don't understand when the around_* callbacks are triggered in relation to before_* and after_* .
...
warning: implicit declaration of function
...s to declare function prototype in header.
Example
main.h
#ifndef MAIN_H
#define MAIN_H
int some_main(const char *name);
#endif
main.c
#include "main.h"
int main()
{
some_main("Hello, World\n");
}
int some_main(const char *name)
{
printf("%s", name);
}
Alternative with one file...
On delete cascade with doctrine2
...ple in order to learn how to delete a row from a parent table and automatically delete the matching rows in the child table using Doctrine2.
...
mongodb count num of distinct values per field/key
...}
},
{ $unwind: "$keywords" },
{
$group: {
_id: {$toLower: '$keywords'},
count: { $sum: 1 }
}
},
{
$match: {
count: { $gte: 2 }
}
},
{ $sort : { count : -1} },
{ $limit : 100 }
]);
that give result ...
System.Threading.Timer in C# it seems to be not working. It runs very fast every 3 second
I've a timer object. I want it to be run every minute. Specifically, it should run a OnCallBack method and gets inactive while a OnCallBack method is running. Once a OnCallBack method finishes, it (a OnCallBack ) restarts a timer.
...
How do I call setattr() on the current module?
...
import sys
thismodule = sys.modules[__name__]
setattr(thismodule, name, value)
or, without using setattr (which breaks the letter of the question but satisfies the same practical purposes;-):
globals()[name] = value
Note: at module scope, the latter is eq...
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 / ...
Conditional HTML Attributes using Razor MVC3
...s" />
If strCSSClass is null then the class attribute won't render at all.
SSSHHH...don't tell. :)
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Match whitespace but not newlines
...ghteen horizontal ones which match \h. \s matches twenty-three characters
All whitespace characters are either vertical or horizontal with no overlap, but they are not proper subsets because \h also matches U+00A0 NO-BREAK SPACE, and \v also matches U+0085 NEXT LINE, neither of which are matched by...
Error: Jump to case label
...code, if foo equals 1, everything is ok, but if it equals 2, we'll accidentally use the i variable which does exist but probably contains garbage.
switch(foo) {
case 1:
int i = 42; // i exists all the way to the end of the switch
dostuff(i);
break;
case 2:
dostuff(i*2); // i is ...