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Django filter queryset __in for *every* item in list
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Summary:
One option is, as suggested by jpic and sgallen in the comments, to add .filter() for each category. Each additional filter adds more joins, which should not be a problem for small set of categories.
There is the aggregation approach. This query would be shorter and...
Why does this loop produce “warning: iteration 3u invokes undefined behavior” and output more than 4
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If during the evaluation of an expression, the result is not mathematically defined or not in the range of
representable values for its type, the behavior is undefined. [ Note: most existing implementations of C++
ignore integer overflows. Treatment of division by zero, forming a remainde...
Pass props to parent component in React.js
...ase of direct parent-child relationship. When parent and child have potentially a lot of intermediaries, check this answer.
Other solutions are missing the point
While they still work fine, other answers are missing something very important.
Is there not a simple way to pass a child's props to...
Byte order mark screws up file reading in Java
...va. Some of the files may have a byte order mark in the beginning, but not all. When present, the byte order gets read along with the rest of the first line, thus causing problems with string compares.
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Can I Install Laravel without using Composer?
I'd like to know if I can install or use the Laravel PHP framework on any web server without using Composer (PHP package/dependency manager) every time?
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Support for “border-radius” in IE
...es! When IE9 is released in Jan 2011.
Let's say you want an even 15px on all four sides:
.myclass {
border-style: solid;
border-width: 2px;
-moz-border-radius: 15px;
-webkit-border-radius: 15px;
border-radius: 15px;
}
IE9 will use the default border-radius, so just make sure you include th...
Map vs Object in JavaScript
...stored at a key. Because of this, Objects have been used as Maps
historically; however, there are important differences between Objects
and Maps that make using a Map better.
An Object has a prototype, so there are default keys in the map.
However, this can be bypassed using map = Object....
“Notice: Undefined variable”, “Notice: Undefined index”, and “Notice: Undefined offset” using PHP
... can be used to detect if a variable has been already initialized. Additionally and more ideal is the solution of empty() since it does not generate a warning or error message if the variable is not initialized.
From PHP documentation:
No warning is generated if the variable does not exist. T...
Evaluating a mathematical expression in a string
...p://pyparsing.wikispaces.com/message/view/home/15549426
'''
__note__ = '''
All I've done is rewrap Paul McGuire's fourFn.py as a class, so I can use it
more easily in other places.
'''
class NumericStringParser(object):
'''
Most of this code comes from the fourFn.py pyparsing example
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Javascript roundoff number to nearest 0.5
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rounding the num*2 is not working for all case..try any decimal like 15.27 => using your formula will give => 15 where in fact it should have returned 15.5. **** I think using toFixed will be better (num*2).toFixed()/2
– sfdx bomb
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