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Is there shorthand for returning a default value if None in Python? [duplicate]
...if x is not null, and the empty string if x is null. I've found it useful for working with databases.
5 Answers
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How can I replace a newline (\n) using sed?
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Append the current and next line to the pattern space via N.
If we are before the last line, branch to the created label $!ba ($! means not to do it on the last line as there should be one final newline).
Finally the substitution replaces every newline with a space on the pattern space (which is th...
Extracting text OpenCV
...e elements (inspired from a LPD):
#include "opencv2/opencv.hpp"
std::vector<cv::Rect> detectLetters(cv::Mat img)
{
std::vector<cv::Rect> boundRect;
cv::Mat img_gray, img_sobel, img_threshold, element;
cvtColor(img, img_gray, CV_BGR2GRAY);
cv::Sobel(img_gray, img_sobel, ...
What is the javascript filename naming convention? [closed]
Should files be named something-with-hyphens.js, camelCased.js, or something else?
5 Answers
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If Python is interpreted, what are .pyc files?
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@froadie: a language is not "interpreted" or "compiled" as such. A specific implementation can be an interpreter or a compiler (or a hybrid or a JIT compiler).
– Joachim Sauer
Jun 8 '10 at 14:41
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Qt events and signal/slots
In the Qt world, what is the difference of events and signal/slots?
10 Answers
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Why not use Double or Float to represent currency?
I've always been told never to represent money with double or float types, and this time I pose the question to you: why?
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Difference between a Message Broker and an ESB
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You can use a transformation broker without a service bus, and vice versa. In terms of specific products I don't think any one is purely one or the other because of the way each complements the other. Some products are stronger in the one area...
How to avoid isset() and empty()
...undefined" and "undefined offset" messages when running on the E_NOTICE error level, because the existence of variables is not explicitly checked using isset() and consorts.
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Does Python have a ternary conditional operator?
If Python does not have a ternary conditional operator, is it possible to simulate one using other language constructs?
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