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When to use references vs. pointers

...going in undefined-behaviour-land; the reference attribute version doesn't allow (without easy to spot tricks) the problem with 1. the reference attribute version is simpler to understand for the user: you have to provide a valid object, not something that could be null. If the behaviour of the fun...
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How do I exit a WPF application programmatically?

... To exit your application you can call System.Windows.Application.Current.Shutdown(); As described in the documentation to the Application.Shutdown method you can also modify the shutdown behavior of your application by specifying a ShutdownMode: Shutdown i...
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Django Passing Custom Form Parameters to Formset

...m functools import partial, wraps from django.forms.formsets import formset_factory ServiceFormSet = formset_factory(wraps(ServiceForm)(partial(ServiceForm, affiliate=request.affiliate)), extra=3) I think this is the cleanest approach, and doesn't affect ServiceForm in any way (i.e. by making it ...
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Can I load a .NET assembly at runtime and instantiate a type knowing only the name?

Is it possible to instantiate an object at runtime if I only have the DLL name and the class name, without adding a reference to the assembly in the project? The class implements a interface, so once I instantiate the class, I will then cast it to the interface. ...
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How to do ToString for a possibly null object?

... | edited Sep 4 at 21:32 answered Oct 21 '10 at 12:56 A...
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How to unit test an object with database queries

I've heard that unit testing is "totally awesome", "really cool" and "all manner of good things" but 70% or more of my files involve database access (some read and some write) and I'm not sure how to write a unit test for these files. ...
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Why doesn't print work in a lambda?

...ed print function if you are using the latest Python 2.x: In [1324]: from __future__ import print_function In [1325]: f = lambda x: print(x) In [1326]: f("HI") HI share | improve this answer ...
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Rails 3 check if attribute changed

... Check out ActiveModel::Dirty (available on all models by default). The documentation is really good, but it lets you do things such as: @user.street1_changed? # => true/false share ...
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Provide an image for WhatsApp link sharing

.... But as soon as you use that link once, this "please note" section starts all over again. Step 1: title Maximum of 65 characters <title>your keyword rich title of the website and/or webpage</title> Step 2: description Maximum of 155 characters <meta name="description" content="des...
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PG::ConnectionBad - could not connect to server: Connection refused

... #2 is a great suggestion: "Check server.log". My error was actually caused by upgrading to Yosemite, the server log said: FATAL: could not open directory "pg_tblspc": No such file or directory. This answer helped me with that problem stackoverflow.com/questions/25970132/… ...