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this.setState isn't merging states as I would expect
...y) here to prevent modification to the existing selected part of the state by creating a shallow copy of it.
Another solution would be to write setStateRecursively() which does recursive merge on a new state and then calls replaceState() with it:
setStateRecursively: function(stateUpdate, callback...
How to get a path to a resource in a Java JAR file
...
you can add 'rsrc:' when you call your resource in order to open it. like new File("rsrc:filename.txt") this will load filename.txt which is packed inside the root of your jar
– gipsh
Jun 16 '16 at 18:45
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Check if table exists and if it doesn't exist, create it in SQL Server 2008
...read, and you don't have to worry about sys.objects vs. sysobjects vs. sys.all_objects
vs. sys.tables. Basic form:
IF object_id('MyTable') is not null
PRINT 'Present!'
ELSE
PRINT 'Not accounted for'
Of course this will show as "Present" if there is any object present with that name. If yo...
How to call base.base.method()?
...Derived
{
public override void Say()
{
Console.WriteLine("Called from Special Derived.");
var ptr = typeof(Base).GetMethod("Say").MethodHandle.GetFunctionPointer();
var baseSay = (Action)Activator.CreateInstance(typeof(Action), this, ptr);
baseSay(...
Offset a background image from the right using CSS
...hat works perfectly:
background: url('/img.png') no-repeat right center;
border-right: 10px solid transparent;
I used it since the CSS3 feature of specifying offsets proposed in the answer marked as solving the question is not supported in browsers so well yet. E.g.
...
count the frequency that a value occurs in a dataframe column
... 2
b 3
s 2
With df.a.value_counts() sorted values (in descending order, i.e. largest value first) are returned by default.
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Singleton: How should it be used
...arginally more reliable in languages without a well-defined initialization order, this usage is still the moral equivalent of a global variable. It's a global variable dressed up in some awkward syntax (foo::get_instance() instead of g_foo, say), but it serves the exact same purpose (a single objec...
How do you test that a Python function throws an exception?
...t ahold of the actual Exception object thrown:
import unittest
def broken_function():
raise Exception('This is broken')
class MyTestCase(unittest.TestCase):
def test(self):
with self.assertRaises(Exception) as context:
broken_function()
self.assertTrue('This i...
Understanding implicit in Scala
..., which means the values will be taken from the context in which they are called. If there is no implicit value of the right type in scope, it will not compile. Since the implicit value must resolve to a single value and to avoid clashes, it's a good idea to make the type specific to its purpose, e....
Count the items from a IEnumerable without iterating?
...as other responders say, being completely ignorant and always iterating in order to count elements.
In many cases where the programmer is just checking if( enumerable.Count != 0 ) using the Any() extension method, as in if( enumerable.Any() ) is far more efficient with linq's lazy evaluation as it...