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Duplicate symbols for architecture x86_64 under Xcode
...at defines an Objective-C class or category. While this option will
typically result in a larger executable (due to additional object code
loaded into the application), it will allow the successful creation of
effective Objective-C static libraries that contain categories on
existing classes...
How to convert CFStringRef to NSString?
...n objects with +1 reference counts, meaning that they need to be released (all CF[Type]Create format functions do this).
The nice thing is that in Cocoa you can safely use autorelease or release to free them up.
share
...
Serializing class instance to JSON
...ps() only knows how to serialize a limited set of object types by default, all built-in types. List here: https://docs.python.org/3.3/library/json.html#encoders-and-decoders
One good solution would be to make your class inherit from JSONEncoder and then implement the JSONEncoder.default() function...
How to JSON serialize sets?
...s.
As shown in the json module docs, this conversion can be done automatically by a JSONEncoder and JSONDecoder, but then you would be giving up some other structure you might need (if you convert sets to a list, then you lose the ability to recover regular lists; if you convert sets to a dictionar...
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...
Why dict.get(key) instead of dict[key]?
...
It allows you to provide a default value if the key is missing:
dictionary.get("bogus", default_value)
returns default_value (whatever you choose it to be), whereas
dictionary["bogus"]
would raise a KeyError.
If omitted...
How do you get the list of targets in a makefile?
...ed rake a bit (a Ruby make program), and it has an option to get a list of all the available targets, eg
20 Answers
...
decorators in the python standard lib (@deprecated specifically)
...r('always', DeprecationWarning) # turn off filter
warnings.warn("Call to deprecated function {}.".format(func.__name__),
category=DeprecationWarning,
stacklevel=2)
warnings.simplefilter('default', DeprecationWarning) # reset filter
...
ModelSerializer using model property
... Meta is optional. If you omit fields, in the above example, you would get all the MyModel fields plus ext_link in the serialized data. And this is really awesome for complex models! EDIT: At least, this is true for djangorestframework==2.3.14.
– e.thompsy
Feb ...
What is the list of possible values for navigator.platform as of today? [closed]
...urate.
The definition
As far as I know there isn't a single public list of all possible `navigator.platform` values, even though the property has been around for quite a bit. To make things worse, the property's definition changed throughout the years. It used to be:
navigator.platform indicates th...