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Recommended way of making React component/div draggable
...React.createClass({
getDefaultProps: function () {
return {
// allow the initial position to be passed in as a prop
initialPos: {x: 0, y: 0}
}
},
getInitialState: function () {
return {
pos: this.props.initialPos,
dragging: false,
rel: null // position...
How to get line count of a large file cheaply in Python?
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You can't get any better than that.
After all, any solution will have to read the entire file, figure out how many \n you have, and return that result.
Do you have a better way of doing that without reading the entire file? Not sure... The best solution will always ...
What are “first class” objects?
...as
any other object.
A first class object is an entity that can be dynamically created, destroyed, passed to a function, returned as a value, and have all the rights as other variables in the programming language have.
Depending on the language, this can
imply:
being expressible as ...
Setting the selected value on a Django forms.ChoiceField
...rying to assign the selected value to a ChoiceField.
If you have already called super().__init__ in your Form class, you should update the form.initial dictionary, not the field.initial property. If you study form.initial (e.g. print self.initial after the call to super().__init__), it will contai...
Return a value if no rows are found in Microsoft tSQL
... S.Id = @SiteId and S.Status = 1 AND
(S.WebUserId = @WebUserId OR S.AllowUploads = 1)
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What does FETCH_HEAD in Git mean?
...it like doing git fetch without arguments (or git remote update), updating all your remote branches, then running git merge origin/<branch>, but using FETCH_HEAD internally instead to refer to whatever single ref was fetched, instead of needing to name things.
...
Which is better in python, del or delattr?
... (foo)
6 LOAD_CONST 1 ('bar')
9 CALL_FUNCTION 2
12 POP_TOP
This translates into the first running slightly faster (but it's not a huge difference – .15 μs on my machine).
Like the others have said, you should really...
What techniques can be used to speed up C++ compilation times?
...ity that takes advantage of caching techniques to speed things up.
Use Parallelism
Many compilers / IDEs support using multiple cores/CPUs to do compilation simultaneously. In GNU Make (usually used with GCC), use the -j [N] option. In Visual Studio, there's an option under preferences to allow it...
Is there a benefit to defining a class inside another class in Python?
What I'm talking about here are nested classes. Essentially, I have two classes that I'm modeling. A DownloadManager class and a DownloadThread class. The obvious OOP concept here is composition. However, composition doesn't necessarily mean nesting, right?
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How to track down a “double free or corruption” error
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If you're using glibc, you can set the MALLOC_CHECK_ environment variable to 2, this will cause glibc to use an error tolerant version of malloc, which will cause your program to abort at the point where the double free is done.
You can set this from gdb by using ...