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Possible to do a MySQL foreign key to one of two possible tables?
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What you're describing is called Polymorphic Associations. That is, the "foreign key" column contains an id value that must exist in one of a set of target tables. Typically the target tables are related in some way, such as being instances of some c...
Reload .profile in bash shell script (in unix)?
I'm new to bash shell scripting, and have come across a challenge. I know I can reload my ".profile" file by just doing:
5 ...
FFmpeg: How to split video efficiently?
I wish to split a large avi video into two smaller consecutive videos. I am using ffmpeg.
9 Answers
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What is the difference between Ruby 1.8 and Ruby 1.9
... Sam's slides. The slideshow is less overwhelming to review, but having it all laid out in a list like this is also helpful.
Ruby 1.9 - Major Features
Performance
Threads/Fibers
Encoding/Unicode
gems is (mostly) built-in now
if statements do not introduce scope in Ruby.
What's changed?
Single ...
What is a stack trace, and how can I use it to debug my application errors?
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In simple terms, a stack trace is a list of the method calls that the application was in the middle of when an Exception was thrown.
Simple Example
With the example given in the question, we can determine exactly where the exception was thrown in the application. Let's have a lo...
How do I mock the HttpContext in ASP.NET MVC using Moq?
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HttpContext is read-only, but it is actually derived from the ControllerContext, which you can set.
controller.ControllerContext = new ControllerContext( context.Object, new RouteData(), controller );
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How to compare if two structs, slices or maps are equal?
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@GeneralLeeSpeaking that's not true. From the cmp documentation: "Pointers are equal if the underlying values they point to are also equal"
– Ilia Choly
Dec 29 '18 at 18:11
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Unnamed/anonymous namespaces vs. static functions
... this case using a static or an unnamed namespace are back to being essentially two ways of doing the exact same thing. For more discussion please see this SO question.
Unnamed namespaces still have the advantage of allowing you to define translation-unit-local types. Please see this SO question ...
ctypes - Beginner
...o testlib.so -fPIC testlib.c
# or... for Mac OS X
$ gcc -shared -Wl,-install_name,testlib.so -o testlib.so -fPIC testlib.c
Then, write a wrapper using ctypes:
testlibwrapper.py
import ctypes
testlib = ctypes.CDLL('/full/path/to/testlib.so')
testlib.myprint()
Now execute it:
$ python testlibwrap...
What are the differences between a HashMap and a Hashtable in Java?
...shMap better for non-threaded applications, as unsynchronized Objects typically perform better than synchronized ones.
Hashtable does not allow null keys or values. HashMap allows one null key and any number of null values.
One of HashMap's subclasses is LinkedHashMap, so in the event that you'd wa...