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Why doesn't list have safe “get” method like dictionary?
...accessing list elements (as the len method is very fast). The .get method allows you to query the value associated with a name, not directly access the 37th item in the dictionary (which would be more like what you're asking of your list).
Of course, you can easily implement this yourself:
def sa...
Adding Core Data to existing iPhone project
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All the CoreData header files are imported in App_Prefix.pch, so the CoreData classes will be available throughout your Project, so you don't have to manually import the header in the files you need them.
So open up Xcode an...
Does using “new” on a struct allocate it on the heap or stack?
...hen you create an instance of a class with the new operator, memory gets allocated on the heap. When you create an instance of a struct with the new operator where does the memory get allocated, on the heap or on the stack ?
...
What's the UIScrollView contentInset property for?
... answered Dec 31 '09 at 1:21
jballjball
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log messages appearing twice with Python Logging
I'm using Python logging, and for some reason, all of my messages are appearing twice.
8 Answers
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List goals/targets in GNU make that contain variables in their definition
...utput from make -pn (i.e. make --print-data-base --dry-run)? It prints out all the variables, rules, implicit rules and which commands will be run in laborious detail.
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“Inner exception” (with traceback) in Python?
...recently started programming in Python. When an exception is thrown I typically want to wrap it in another exception that adds more information, while still showing the full stack trace. It's quite easy in C#, but how do I do it in Python?
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node.js global variables?
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Globals are generally to be avoided, but if you really want to use them. The 3 statements below are all equivalent and will assign a var to the global scope: GLOBAL._ = require('underscore'); global._ = require('underscore'); _ = require('und...
Is there a difference between “==” and “is”?
... a
True
In your case, the second test only works because Python caches small integer objects, which is an implementation detail. For larger integers, this does not work:
>>> 1000 is 10**3
False
>>> 1000 == 10**3
True
The same holds true for string literals:
>>> "a" i...
What does if __name__ == “__main__”: do?
...ngs:
it sets a few special variables like __name__, and then
it executes all of the code found in the file.
Let's see how this works and how it relates to your question about the __name__ checks we always see in Python scripts.
Code Sample
Let's use a slightly different code sample to explore ho...