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NSString property: copy or retain?
...s usually better to retain them rather than copy in order to avoid wasting time and memory.
– Rob Napier
Apr 27 '10 at 0:08
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What is the difference between .text, .value, and .value2?
...roblem is that Excel does not have a true Date data-type - excel dates and times are just doubles that depend on whatever format has been applied or changed by the user to appear as dates, times or currency or just a number. So Value is coercing an Excel double to a VBA date but Value2 is not doing ...
What's the valid way to include an image with no src?
... (Some browsers would simply make the invalid request and wait for them to time out.)
This was tested in Chrome, Safari 5, FF 3.6, and IE 6/7/8, but I would expect it to work in any browser, as it should be the network layer which kills any attempted request.
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How to recursively delete an entire directory with PowerShell 2.0?
...this twice when run on a directory that contains subdirectories. The first time, there will be a lot of "The directory is not empty" errors. The second time, it completes with no errors.
– Kristopher Johnson
Dec 2 '11 at 20:03
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How to debug PDO database queries?
... with prepared statements : if you have to execute the same query a lot of times, it'll only be sent to the DB and prepared once : for each execution, only the data will be sent.
– Pascal MARTIN
Mar 9 '10 at 18:06
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In C#, What is a monad?
... got as input", so that we don't need to explicitly specify socket lots of times:
new socket() >>= bind(...) >>= connect(...) >>= send(...);
The formal definition is a bit more complicated since you have to worry about how to get the result of one function as an input to the nex...
Is there a rule-of-thumb for how to divide a dataset into training and validation sets?
...ith different amounts of training data: randomly sample 20% of it, say, 10 times and observe performance on the validation data, then do the same with 40%, 60%, 80%. You should see both greater performance with more data, but also lower variance across the different random samples
To get a handle on...
Is it not possible to stringify an Error using JSON.stringify?
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First time I've heard monkey patching :)
– Chris Prince
Jun 18 '16 at 17:27
2
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How exactly does work?
...te. I was addressing the fact that the wrong answer wasn't selected at the time the question was asked. Perhaps you should police the folks spreading false assessments about the community improperly selecting answers, instead of folks trying to remind people that things change over time, and contex...
Selecting and manipulating CSS pseudo-elements such as ::before and ::after using jQuery
...e combined with the second technique if the CSS can't be prepared ahead of time:
var str = "bar";
document.styleSheets[0].addRule('p:before', 'content: attr(data-before);');
$('p').on('click', function () {
$(this).attr('data-before', str);
});
var str = "bar";
document.styleSheets[0...