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How do you represent a graph in Haskell?
...n haskell using algebraic data types. But how would you go about typographically representing a graph? It seems that you need to have pointers. I'm guessing you could have something like
...
Instance v state variables in react.js
...d (which should only be done by setState as suggested in a comment), React calls render and makes any necessary changes to the real DOM.
Because the value of timeout has no effect on the rendering of your component, it shouldn't live in state. Putting it there would cause unnecessary calls to rende...
How to cancel a Task in await?
... below, and it works to some point. The CancelNotification method DOES get called, which makes you think the task was cancelled, but in the background the task keeps running, then after it's completed, the status of the Task is always completed and never cancelled. Is there a way to completely halt ...
Is there a 'box-shadow-color' property?
... height: 30px;
box-shadow: 1px 1px 25px var(--box-shadow-color); /* Calling the variable */
}
.box-shadow:hover {
--box-shadow-color: #ff0000; /* Changing the value of the variable */
}
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Creating an instance of class
...ecause Foo is not a POD type.
/* 3 */ Foo foo3;
Creates a Foo object called foo3 in automatic storage.
/* 4 */ Foo foo4 = Foo::Foo();
Uses copy-initialization to create a Foo object called foo4 in automatic storage.
/* 5 */ Bar* bar1 = new Bar ( *new Foo() );
Uses Bar's conversion ...
PHP: exceptions vs errors?
... of code that will insert a row into a database. It is possible that this call fails (duplicate ID) - you will want to have a "Error" which in this case is an "Exception". When you are inserting these rows, you can do something like this
try {
$row->insert();
$inserted = true;
} catch (Exc...
Is there any free OCR library for Android? [closed]
...
There is already a Tesseract JNI interface for Java called Tessjeract. code.google.com/p/tesjeract
– sventechie
Dec 4 '09 at 19:21
1
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How to get element by class name? [duplicate]
...use of its magic length property:
var arrFromList = Array.prototype.slice.call(y);
//or as per AntonB's comment:
var arrFromList = [].slice.call(y);
As yckart suggested querySelector('.foo') and querySelectorAll('.foo') would be preferable, though, as they are, indeed, better supported (93.99% vs...
Javascript when to use prototypes
...he problem with JavaScript is that naked constructor functions require the caller to remember to prefix them with new or otherwise they typically don't work. There is no good reason for this. jQuery gets it right by hiding that nonsense behind an ordinary function, $, so you don't have to care how t...
Numpy `logical_or` for more than two arguments
... 'logical_or'>
You can of course chain together multiple logical_or calls like this:
>>> x = np.array([True, True, False, False])
>>> y = np.array([True, False, True, False])
>>> z = np.array([False, False, False, False])
>>> np.logical_or(np.logical_or(x,...