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Test if a variable is a list or tuple
... excludes custom sequences, iterators, and other things that you might actually need. However, sometimes you need to behave differently if someone, for instance, passes a string. My preference there would be to explicitly check for str or unicode like so:
import types
isinstance(var, types.String...
What's the use of ob_start() in php?
...Think of ob_start() as saying "Start remembering everything that would normally be outputted, but don't quite do anything with it yet."
For example:
ob_start();
echo("Hello there!"); //would normally get printed to the screen/output to browser
$output = ob_get_contents();
ob_end_clean();
There a...
How to take the first N items from a generator or list in Python? [duplicate]
...imple syntax: array[start:stop:step]
You can omit any parameter. These are all valid: array[start:], array[:stop], array[::step]
Slicing a generator
import itertools
top5 = itertools.islice(my_list, 5) # grab the first five elements
You can't slice a generator directly in Python. itertools.i...
CSS styling in Django forms
...ling, if you need an unique identifier its better to use id. Second its usually the template side's responsobilty to do exaclty this, Esspecially if you are going to access this class via frontend methods (js, css). I didn't say your answer is wrong. In my opinion its just bad practice (esspecially ...
How to check if an int is a null
I have an object called Person .
8 Answers
8
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Check if one list contains element from the other
...ked, it works perfect as long as you have right equals implemented. that's all matters!
– Syed Siraj Uddin
Feb 8 '19 at 12:51
add a comment
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Matching an empty input box using CSS
...e present in the input tag. Tested in Chrome - not sure if this counts for all browsers.
– Berend
Mar 17 '17 at 6:23
10
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Rails raw SQL example
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and then you'd need to call values on this PG::Result object to get the results array
– jobwat
Mar 26 '14 at 1:00
3
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What's the difference between using CGFloat and float?
I tend to use CGFloat all over the place, but I wonder if I get a senseless "performance hit" with this. CGFloat seems to be something "heavier" than float, right? At which points should I use CGFloat, and what makes really the difference?
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ATL COM开发入门（二）（ActiveX/COM组件回调JS） - C/C++ - 清泛网 - 专注C/C++及内核技术
...patch;
UINT nRet = SetTimer(NULL, // handle to main window
ID_TIMER, // 定时器标识
1000, // 1 秒间隔
(TIMERPROC)TimerProc); // 回调函数
return S_OK;
}
TimerProc回调函数：
IDispatch* gIDispatch = NULL;
#define ID_TIMER 1
...