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On design patterns: When should I use the singleton?
...ptable" reasons to use a Singleton.
One reason that tends to come up over and over again on the internets is that of a "logging" class (which you mentioned). In this case, a Singleton can be used instead of a single instance of a class because a logging class usually needs to be used over and over ...
Setting PayPal return URL and making it auto return?
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Log in to your PayPal account at https://www.paypal.com or https://www.sandbox.paypal.com
The My Account Overview page appears.
Click the gear icon top right.
The Profile Summary page appears.
Click the My Selling Preferences link in the left column.
Under the Selling Online section, ...
How do I get the row count of a pandas DataFrame?
I'm trying to get the number of rows of dataframe df with Pandas, and here is my code.
14 Answers
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Ruby: What is the easiest way to remove the first element from an array?
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Note this mutates the array and returns nil on an empty array. See drop for an alternative, as mentioned in the other answer.
– Jay
Oct 15 '15 at 21:37
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How are GCC and g++ bootstrapped?
This has been bugging me for a while. How do GCC and g++ compile themselves?
1 Answer
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Use 'import module' or 'from module import'?
...use import module or from module import . I've just started with Python and I'm trying to start off with best practices in mind.
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Can I install Python 3.x and 2.x on the same Windows computer?
I'm running Windows and the shell/OS automatically runs Python based on the registry settings when you run a program on the command line. Will this break if I install a 2.x and 3.x version of Python on the same machine?
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Can you use a trailing comma in a JSON object?
...ed to worry about all browsers.
In general I try turn the problem around, and add the comma before the actual value, so you end up with code that looks like this:
s.append("[");
for (i = 0; i < 5; ++i) {
if (i) s.append(","); // add the comma only if this isn't the first entry
s.appendF("\"...
filters on ng-model in an input
I have a text input and I don't want to allow users to use spaces, and everything typed will be turned into lowercase.
8 An...
How do I check if a string is valid JSON in Python?
... can do something else with it. So far, I've only gotten the error message and type.
– Joey Blake
Apr 1 '11 at 12:36
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