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Linq code to select one item
...ion methods directly like:
var item = Items.First(i => i.Id == 123);
And if you don't want to throw an error if the list is empty, use FirstOrDefault which returns the default value for the element type (null for reference types):
var item = Items.FirstOrDefault(i => i.Id == 123);
if (ite...
namedtuple and default values for optional keyword arguments
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I subclassed namedtuple and overrode the __new__ method:
from collections import namedtuple
class Node(namedtuple('Node', ['value', 'left', 'right'])):
__slots__ = ()
def __new__(cls, value, left=None, right=None):
return super(Nod...
#1071 - Specified key was too long; max key length is 767 bytes
When I executed the following command:
34 Answers
34
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What does glLoadIdentity() do in OpenGL?
I'm new to OpenGL and I'm a little overwhelmed with all of the random functions that I have in my code. They work and I know when to use them, but I don't know why I need them or what they actually do.
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Eclipse returns error message “Java was started but returned exit code = 1”
...ine):
/!\ make sure, that the -vm option occurs before the -vmargs command.
Everything after -vmargs is passed directly to the JVM.
-vm
c:/wherever/java/jdk1.6.0_21/jre/bin/server/jvm.dll
-vmargs...
...to your eclipse.ini file, pointing to the JDK you want to use, and check that the req...
String concatenation vs. string substitution in Python
In Python, the where and when of using string concatenation versus string substitution eludes me. As the string concatenation has seen large boosts in performance, is this (becoming more) a stylistic decision rather than a practical one?
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How to tell which version of a gem a rails app is using
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In Rails 3 and Rails 4, use bundle show
In Rails 2, rake gems will print out what gems, dependencies, and versions are installed, frozen, etc.
share
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Why is isNaN(null) == false in JS?
...pts to convert the passed parameter to a number1 (equivalent to Number(x)) and then tests if the value is NaN. If the parameter can't be converted to a number, Number(x) will return NaN2. Therefore, if the conversion of parameter x to a number results in NaN, it returns true; otherwise, it returns f...
Rails respond_with: how does it work?
I've been reading here and there about how cool the respond_with method is in Rails 3. But I can't even find a reference to it in either the Rails APIs or by searching the source. Can anyone either explain to me how it works (what options you can use, etc) or point me to the place it's actually im...
Random color generator
Given this function, I want to replace the color with a random color generator.
54 Answers
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