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What is the right way to override a setter method in Ruby on Rails?
I am using Ruby on Rails 3.2.2 and I would like to know if the following is a "proper"/"correct"/"sure" way to override a setter method for a my class attribute.
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Hidden features of Windows batch files
...
PUSHD path
Takes you to the directory specified by path.
POPD
Takes you back to the directory you "pushed" from.
share
edited Apr 6 '11 at 12:49
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How to initialize static variables
...rse non-trivial expressions in initializers.
I prefer to work around this by adding code right after definition of the class:
class Foo {
static $bar;
}
Foo::$bar = array(…);
or
class Foo {
private static $bar;
static function init()
{
self::$bar = array(…);
}
}
Foo::init();
...
Simple C example of doing an HTTP POST and consuming the response
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A message has a header part and a message body separated by a blank line. The blank line is ALWAYS needed even if there is no message body. The header starts with a command and has additional lines of key value pairs separated by a colon and a space. If there is a message body, ...
How to select rows with one or more nulls from a pandas DataFrame without listing columns explicitly
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If you want to filter rows by a certain number of columns with null values, you may use this:
df.iloc[df[(df.isnull().sum(axis=1) >= qty_of_nuls)].index]
So, here is the example:
Your dataframe:
>>> df = pd.DataFrame([range(4), [0, np.NaN,...
How to explain callbacks in plain english? How are they different from calling one function from ano
...ll-back-function as parameters taking the result created with the variable by the original function and pass it in the call-back-function for further processing. example: func1(a, callback_func){ v = a + 1} and there is predefined call back function: callback_func(v){return v+1;} this will increase ...
Does Android support near real time push notification?
...solution:
The Android client must maintain a persistent TCP connection by waking up periodically
to send a heartbeat to the XMPP server.
This clearly imposes a cost in terms of power usage. An estimate of this cost is
provided below:
Using a 1400mAh battery (as supplied in the Nexu...
Xcode “The private key for is not installed on this mac - distributing”
...rom the iOS developer website.
Generate a new iOS Distribution Certificate by going to XCode Preferences->Accounts->View Details and then clicking the + underneath the list of signing identities.
Go back to the developer website and make sure all your provisioning profiles are configured with ...
ruby convert array into function arguments
... imageUploader: {
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How can I use numpy.correlate to do autocorrelation?
... the convolution of a with the reverse of v and giving the results clipped by the specified mode. The definition of convolution, C(t)=∑ -∞ < i < ∞ aivt+i where -∞ < t < ∞, allows for results from -∞ to ∞, but you obviously can't store an infinitely long array. So it has to...