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Using NSPredicate to filter an NSArray based on NSDictionary keys
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It should work - as long as the data variable is actually an array containing a dictionary with the key SPORT
NSArray *data = [NSArray arrayWithObject:[NSMutableDictionary dictionaryWithObject:@"foo" forKey:@"BAR"]];
NSArray *filtered = [data filteredArrayUsingPredicate:[N...
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 ...
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 ...
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...
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...
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...
Is the “struct hack” technically undefined behavior?
...rictly conforming with the C Standard, although it does seem to work under all known implementations. (Compilers which check array bounds carefully might issue warnings.)
The rationale behind the 'strictly conforming' bit is in the spec, section J.2 Undefined behavior, which includes in the list o...
UPDATE multiple tables in MySQL using LEFT JOIN
I have two tables, and want to update fields in T1 for all rows in a LEFT JOIN.
5 Answers
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