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throw new std::exception vs throw std::exception
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The conventional way to throw and catch exceptions is to throw an exception object and to catch it by reference (usually const reference). The C++ language requires the compiler to generate the appropriate code to construct the exception object and to pro...
How do I save and restore multiple variables in python?
I need to save about a dozen objects to a file and then restore them later.
I've tried to use a for loop with pickle and shelve but it didn't work right.
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Rails extending ActiveRecord::Base
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Create a file in the config/initializers directory called extensions.rb and add the following line to the file:
require "active_record_extension"
Inheritance (Preferred)
Refer to Toby's answer.
Monkey patching (Should be avoided)
Create a file in the config/initializers directory called act...
Flatten nested dictionaries, compressing keys
...iterating the dict by key/value, creating new keys for your new dictionary and creating the dictionary at final step.
import collections
def flatten(d, parent_key='', sep='_'):
items = []
for k, v in d.items():
new_key = parent_key + sep + k if parent_key else k
if isinstan...
Does async(launch::async) in C++11 make thread pools obsolete for avoiding expensive thread creation
...rong. I was under the impression that Linux thread creation was very cheap and after testing I determined that the overhead of function call in a new thread vs. a normal one is enormous. The overhead for creating a thread to handle a function call is something like 10000 or more times slower than a ...
How do I determine height and scrolling position of window in jQuery?
I need to grab the height of the window and the scrolling offset in jQuery, but I haven't had any luck finding this in the jQuery docs or Google.
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How are parameters sent in an HTTP POST request?
...or a post looks like one for a get, but with the verb POST instead of GET, and a content type value (and an optional content length value) as the request has content (body). Every type of request has a header, some types also have a body.
– Guffa
Jun 28 '16 at ...
What is memory fragmentation?
... symptom of memory fragmentation is that you try to allocate a large block and you can't, even though you appear to have enough memory free. Another possible consequence is the inability of the process to release memory back to the OS (because each of the large blocks it has allocated from the OS, f...
When splitting an empty string in Python, why does split() return an empty list while split('\n') re
I am using split('\n') to get lines in one string, and found that ''.split() returns an empty list, [] , while ''.split('\n') returns [''] . Is there any specific reason for such a difference?
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“From View Controller” disappears using UIViewControllerContextTransitioning
I got one problem and i have described it below.
17 Answers
17
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