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What is the purpose of backbone.js?
...
Backbone.js is basically an uber-light framework that allows you to structure your Javascript code in an MVC (Model, View, Controller) fashion where...
Model is part of your code that retrieves and populates the data,
View is the HTML repres...
How to merge 2 List and removing duplicate values from it in C#
...return set. This is different
behavior to the Concat
method, which returns all the elements
in the input sequences including
duplicates.
List<int> list1 = new List<int> { 1, 12, 12, 5};
List<int> list2 = new List<int> { 12, 5, 7, 9, 1 };
List<int> ulist = list1.Union(l...
How do I avoid capturing self in blocks when implementing an API?
...ied inside the block (we're not doing that) but also they are not automatically retained when the block is retained (unless you are using ARC). If you do this, you must be sure that nothing else is going to try to execute the block after the MyDataProcessor instance is released. (Given the structure...
Why prefer two's complement over sign-and-magnitude for signed numbers?
...o add them.
Two's complement addition is very simple. You add numbers normally and any carry bit at the end is discarded. So they're added as follows:
0010
+ 1111
=10001
= 0001 (discard the carry)
0001 is 1, which is the expected result of "2+(-1)".
But in your "intuitive" method, adding is m...
How do I modify fields inside the new PostgreSQL JSON datatype?
...a":[null,{"b":[1,2,3]}]}'
For inserting into JSON array (while preserving all of the original values), the jsonb_insert() function can be used (in 9.6+; this function only, in this section):
SELECT jsonb_insert('{"a":[null,{"b":[1]}]}', '{a,1,b,0}', jsonb '2')
-- will yield jsonb '{"a":[null,{"b":[...
Dynamically set local variable [duplicate]
How do you dynamically set local variable in Python (where the variable name is dynamic)?
7 Answers
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Define a lambda expression that raises an Exception
...ur goal is to avoid a def, this obviously doesn't cut it. It does, however allow you to conditionally raise exceptions, e.g.:
y = lambda x: 2*x if x < 10 else raise_(Exception('foobar'))
Alternatively you can raise an exception without defining a named function. All you need is a strong stom...
The tilde operator in Python
...a unary operator (taking a single argument) that is borrowed from C, where all data types are just different ways of interpreting bytes. It is the "invert" or "complement" operation, in which all the bits of the input data are reversed.
In Python, for integers, the bits of the twos-complement repr...
node.js require all files in a folder?
How do I require all files in a folder in node.js?
14 Answers
14
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Format SQL in SQL Server Management Studio
In Visual Studio & other IDEs, you can easily auto format your code with a keyboard shortcut, through the menu, or automatically as you type.
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