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New self vs. new static
...ay is the use of late static binding like return new static($options); , if I convert this to return new self($options) will I get the same results?
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Why is the minimalist, example Haskell quicksort not a “true” quicksort?
...(1), but not (2). How (2) is done may not be obvious if you don't already know the technique!
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What's the “average” requests per second for a production web application?
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@user :-D Yes, it's pretty much historical now. It was a useful answer for me at the time, though! :-)
– Peter K.
Sep 14 '17 at 10:59
add a com...
How do you delete an ActiveRecord object?
...out a primary key
Note: from @hammady's comment, user.destroy won't work if User model has no primary key.
Note 2: From @pavel-chuchuva's comment, destroy_all with conditions and delete_all with conditions has been deprecated in Rails 5.1 - see guides.rubyonrails.org/5_1_release_notes.html
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fetch in git doesn't get all branches
...d the origin remote, and recreated it. That seems to have fixed it. Don't know why.
remove with:
git remote rm origin
and recreate with:
git remote add origin <git uri>
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Why is UICollectionViewCell's outlet nil?
...orrect (correct identifier & class) it refused to connect the outlets. now it works. sweet!
– Joris Weimar
Oct 9 '14 at 19:36
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Python memory usage of numpy arrays
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I use this code to get a listing of all of them and their size.
Not sure if locals() or globals() is better here.
import sys
import numpy
from humanize import naturalsize
for size, name in sorted(
(value.nbytes, name)
for name, value in locals().items()
if isinstance(value, numpy.n...
Add & delete view from Layout
...this);
lp.addView(new Button(this));
lp.addView(new ImageButton(this));
// Now remove them
lp.removeViewAt(0); // and so on
If you have xml layout then no need to add dynamically.just call
lp.removeViewAt(0);
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Truncating floats in Python
...float f to n decimal places without rounding'''
s = '{}'.format(f)
if 'e' in s or 'E' in s:
return '{0:.{1}f}'.format(f, n)
i, p, d = s.partition('.')
return '.'.join([i, (d+'0'*n)[:n]])
This is valid in Python 2.7 and 3.1+. For older versions, it's not possible to get the ...
How to catch curl errors in PHP
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You can use the curl_error() function to detect if there was some error. For example:
$ch = curl_init();
curl_setopt($ch, CURLOPT_URL, $your_url);
curl_setopt($ch, CURLOPT_FAILONERROR, true); // Required for HTTP error codes to be reported via our call to curl_error($ch)
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