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Reverse of JSON.stringify?
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JSON.stringify and JSON.parse are almost oposites, and "usually" this kind of thing will work:
var obj = ...;
var json = JSON.stringify(obj);
var obj2 = JSON.parse(json);
so that obj and obj2 are "the same".
However there are some limitations to be aware of.
Often these issues ...
Rails: How do I create a default value for attributes in Rails activerecord's model? [duplicate]
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add_column :status, :string, :default => "P"
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OR
You can use a callback, before_save
class Task < ActiveRecord::Base
before_save :default_values
def default_values
self.status ||= 'P' # note self.status = 'P' if self.status.nil? might be safer (per @frontendbeauty)
end
end
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What is more efficient? Using pow to square or just multiply it with itself?
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I tested the performance difference between x*x*... vs pow(x,i) for small i using this code:
#include <cstdlib>
#include <cmath>
#include <boost/date_time/posix_time/posix_time.hpp>
inline boost::posix_time::ptime now()
{
return boost::posix_time::microsec_clock::local_t...
What are advantages of Artificial Neural Networks over Support Vector Machines? [closed]
...s exactly the number of training samples (though that mainly occurs with small training sets or in degenerate cases) and in general its model size scales linearly. In natural language processing, SVM classifiers with tens of thousands of support vectors, each having hundreds of thousands of features...
How to test Spring Data repositories?
...epositories reasonably for a simple reason: it's way to cumbersome to mock all the parts of the JPA API we invoke to bootstrap the repositories. Unit tests don't make too much sense here anyway, as you're usually not writing any implementation code yourself (see the below paragraph on custom impleme...
Is It Possible to NSLog C Structs (Like CGRect or CGPoint)?
... With AppKit on OS X you would need to convert to an NSPoint and then call NSStringFromPoint. For example: NSStringFromPoint(NSPointFromCGPoint(point))
– Alex
Aug 22 '12 at 17:56
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Overriding Binding in Guice
...er be injecting mock or fake objects by hand.
On the other hand, if you really want to replace a single binding, you could use Modules.override(..):
public class ProductionModule implements Module {
public void configure(Binder binder) {
binder.bind(InterfaceA.class).to(ConcreteA.class...
Serializing an object as UTF-8 XML in .NET
...o a string again, so its no longer in UTF-8, but back in UTF-16 (though ideally its best to consider strings at a higher level than any encoding, except when forced to do so).
To get the actual UTF-8 octets you could use:
var serializer = new XmlSerializer(typeof(SomeSerializableObject));
var mem...
Is char signed or unsigned by default?
... is 100% equivalent to declaring it as signed int. This is always true for all compilers and architectures.
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How do you convert epoch time in C#?
...d if you need the DateTime object instead of DateTimeOffset, then you can call the DateTime property
DateTime dateTime = dateTimeOffset .DateTime;
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