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How to create a new database after initally installing oracle database 11g Express Edition?
I have installed Oracle Database 11g Express Edition on my pc (windows 7)
and I have installed Oracle SQL Developer as well.
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How can I get nth element from a list?
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Personally I can't comprehend how an at-index accessor that doesn't return a Maybe type is acceptable as idiomatic Haskell. [1,2,3]!!6 will give you a runtime error. It could very easily be avoided if !! had the type [a] -> Int ...
What is the copy-and-swap idiom?
...s arguably the most nuanced and difficult. How should it be done? What pitfalls need to be avoided?
The copy-and-swap idiom is the solution, and elegantly assists the assignment operator in achieving two things: avoiding code duplication, and providing a strong exception guarantee.
How does it wor...
Immutability of Strings in Java
...t, and changing a reference. s2 still points to the same object as we initially set s1 to point to. Setting s1 to "Help!" only changes the reference, while the String object it originally referred to remains unchanged.
If strings were mutable, we could do something like this:
String s1 = "Hello";
St...
Proper use of beginBackgroundTaskWithExpirationHandler
...l need to wrap it in a background task. It's also very important that you call endBackgroundTask when you're finished - otherwise the app will be killed after its allotted time has expired.
Mine tend look something like this:
- (void) doUpdate
{
dispatch_async(dispatch_get_global_queue(DISPAT...
Recursively remove files
... Yes, that is what the print0 and the -0 to xargs is for. Normally it wouldn't handle spaces correctly, however with print0 it will print the filename with a null character at the end of the line, which xarg with -0 will then use to pass the full path to xargs without a chance of having...
How to add an integer to each element in a list?
...ition, but if you have a more complex function that you needed to apply to all the elements then map may be a good fit.
In your example it would be:
>>> map(lambda x:x+1, [1,2,3])
[2,3,4]
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Asserting successive calls to a mock method
Mock has a helpful assert_called_with() method . However, as far as I understand this only checks the last call to a method.
If I have code that calls the mocked method 3 times successively, each time with different parameters, how can I assert these 3 calls with their specific parameters?
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Undefined symbols for architecture i386: _OBJC_CLASS_$_SKPSMTPMessage", referenced from: error
...r the "Compile Sources" step of the "Build Phases" tab of your target. Normally Xcode does this for you, but sometimes it loses the plot and you need to add the .m file manually.
To do this:
TargetSettings -> Build Phases -> Compile Sources -> add your .m class ->Build and Run
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In Python, how can you load YAML mappings as OrderedDicts?
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Update: In python 3.6+ you probably don't need OrderedDict at all due to the new dict implementation that has been in use in pypy for some time (although considered CPython implementation detail for now).
Update: In python 3.7+, the insertion-order preservation nature of dict objects h...