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How can I get a precise time, for example in milliseconds in Objective-C?
...timeIntervalSince* methods will return a NSTimeInterval which is a double with sub-millisecond accuracy. NSTimeInterval is in seconds, but it uses the double to give you greater precision.
In order to calculate millisecond time accuracy, you can do:
// Get a current time for where you want to star...
Get name of caller function in PHP?
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edited Nov 25 '15 at 18:16
Community♦
111 silver badge
answered Oct 10 '08 at ...
What really happens in a try { return x; } finally { x = null; } statement?
...- at the IL level you can't return from inside an exception-handled block. It essentially stores it in a variable and returns afterwards
i.e. similar to:
int tmp;
try {
tmp = ...
} finally {
...
}
return tmp;
for example (using reflector):
static int Test() {
try {
return SomeNu...
Super-simple example of C# observer/observable with delegates
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The observer pattern is usually implemented with events.
Here's an example:
using System;
class Observable
{
public event EventHandler SomethingHappened;
public void DoSomething() =>
SomethingHappened?.Invoke(this, EventArgs.Empty);
}
class Obser...
How to check whether a variable is a class or not?
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edited Apr 16 '16 at 23:23
Eric Leschinski
114k4949 gold badges368368 silver badges313313 bronze badges
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How do I install cygwin components from the command line?
...o tool specifically in the 'setup.exe' installer that offers the
functionality of apt-get. There is, however, a command-line package installer
for Cygwin that can be downloaded separately, but it is not entirely stable and
relies on workarounds.
apt-cyg: http://github.com/transcode-open/apt-cyg
C...
How to redirect to a 404 in Rails?
...'d like to 'fake' a 404 page in Rails. In PHP, I would just send a header with the error code as such:
11 Answers
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Remove a string from the beginning of a string
...
Plain form, without regex:
$prefix = 'bla_';
$str = 'bla_string_bla_bla_bla';
if (substr($str, 0, strlen($prefix)) == $prefix) {
$str = substr($str, strlen($prefix));
}
Takes: 0.0369 ms (0.000,036,954 seconds)
And with:
$prefix...
django admin - add custom form fields that are not part of the model
I have a model registered in the admin site. One of its fields is a long string expression. I'd like to add custom form fields to the add/update page of this model in the admin that based on these fields values I will build the long string expression and save it in the relevant model field.
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Reverse / invert a dictionary mapping
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For Python 2.7.x
inv_map = {v: k for k, v in my_map.iteritems()}
For Python 3+:
inv_map = {v: k for k, v in my_map.items()}
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