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Django 1.7 - makemigrations not detecting changes
... may happen due to the following reasons:
You did not add the app in INSTALLED_APPS list in settings.py
(You have to add either the app name or the dotted path to the subclass of AppConfig in apps.py in the app folder, depending on the version of django you are using). Refer documentation: INST...
Greenlet Vs. Threads
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Greenlets provide concurrency but not parallelism. Concurrency is when code can run independently of other code. Parallelism is the execution of concurrent code simultaneously. Parallelism is particularly useful when there's a lot of work to be done in userspace, an...
The relationship could not be changed because one or more of the foreign-key properties is non-nulla
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You should delete old child items thisParent.ChildItems one by one manually. Entity Framework doesn't do that for you. It finally cannot decide what you want to do with the old child items - if you want to throw them away or if you want to keep and assign them to other parent entities. You must ...
Why can't C compilers rearrange struct members to eliminate alignment padding? [duplicate]
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There are multiple reasons why the C compiler cannot automatically reorder the fields:
The C compiler doesn't know whether the struct represents the memory structure of objects beyond the current compilation unit (for example: a foreign library, a file on disc, network data, CPU page ...
JavaScript function similar to Python range()
...uple of additional defensive checks - ensure that the arguments passed are all coercible to numbers and ensure that stop is greater than start (and swap them if not).
– Russ Cam
Nov 25 '11 at 18:46
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What is the definition of “interface” in object oriented programming
... one of the more overloaded and confusing terms in development.
It is actually a concept of abstraction and encapsulation. For a given "box", it declares the "inputs" and "outputs" of that box. In the world of software, that usually means the operations that can be invoked on the box (along with ar...
See changes to a specific file using git
...s, but, as far as I understood, it is directory based. This means it gives all the changes of all files on the current directory.
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Python dictionary from an object's fields
...a dictionary from an arbitrary object, it's sufficient to use __dict__. Usually, you'll declare your methods at class level and your attributes at instance level, so __dict__ should be fine. For example:
>>> class A(object):
... def __init__(self):
... self.b = 1
... self.c = 2
....
JavaScript and Threads
...onBat JavaScript Benchmark (first link)
The Gears plugin can also be installed in Firefox.
Safari 4, and the WebKit nightlies have worker threads:
JavaScript Ray Tracer
Chrome has Gears baked in, so it can do threads, although it requires a confirmation prompt from the user (and it uses a d...
Java Reflection: How to get the name of a variable?
...they are in scope.
Perhaps a byte-code engineering library like ASM would allow you to inspect this information at runtime. The only reasonable place I can think of for needing this information is in a development tool, and so byte-code engineering is likely to be useful for other purposes too.
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