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How to find if directory exists in Python
...en classes are callable. Also, functions are first-class values in Python, and you can use them without the parentheses notation, like in existing = filter(os.path.isdir(['/lib', '/usr/lib', '/usr/local/lib'])
– phihag
Mar 30 '13 at 7:38
...
Is there a cross-browser onload event when clicking the back button?
... does nothing. But somehow this seems to trigger a reload in Safari, Opera and Mozilla -- no matter what the event handler contains.
[edit(Nickolay): here's why it works that way: webkit.org, developer.mozilla.org. Please read those articles (or my summary in a separate answer below) and consider w...
How to skip over an element in .map()?
...tion would have kept it.
update — This question gets a lot of attention, and I'd like to add the following clarifying remark. The purpose of .map(), as a concept, is to do exactly what "map" means: transform a list of values into another list of values according to certain rules. Just as a paper m...
How to set commands output as a variable in a batch file
...
FOR /F "tokens=* USEBACKQ" %%F IN (`command`) DO (
SET var=%%F
)
ECHO %var%
I always use the USEBACKQ so that if you have a string to insert or a long file name, you can use your double quotes without screwing up the command.
Now if your output will contain mult...
What is your favorite C programming trick? [closed]
...[] = {
#include "normals.txt"
};
(more or less, I don't have the code handy to check it now).
Since then, a new world of creative use of the preprocessor opened in front of my eyes. I no longer include just headers, but entire chunks of code now and then (it improves reusability a lot) :-p
Tha...
Android: Share plain text using intent (to all messaging apps)
...e as:
/*Create an ACTION_SEND Intent*/
Intent intent = new Intent(android.content.Intent.ACTION_SEND);
/*This will be the actual content you wish you share.*/
String shareBody = "Here is the share content body";
/*The type of the content is text, obviously.*/
intent.setType(...
CSS force image resize and keep aspect ratio
I am working with images, and I ran across a problem with aspect ratios.
23 Answers
23...
serve current directory from command line
could someone give me a hint, howto serve the current directory from command line with ruby? it would be great, if i can have some system wide configuration (e.g. mime-types) and simply launch it from every directory.
...
Is C++ context-free or context-sensitive?
...uring-complete, since it shows a program which is syntactically correct if and only if a given integer is prime.
So I assert that C++ is neither context-free nor context-sensitive.
If you allow arbitrary symbol sequences on both sides of any production, you produce an Type-0 grammar ("unrestricted...
Design patterns or best practices for shell scripts [closed]
...
I wrote quite complex shell scripts and my first suggestion is "don't". The reason is that is fairly easy to make a small mistake that hinders your script, or even make it dangerous.
That said, I don't have other resources to pass you but my personal experienc...