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What is the proper way to check for null values?
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I dislike this because if you have any other type of object stuffed in the session than what you expect you may be hiding some subtle bugs in your program. I'd rather use a safe cast because I think it's likely to surface errors faster. It also a...
passing several arguments to FUN of lapply (and others *apply)
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If you look up the help page, one of the arguments to lapply is the mysterious .... When we look at the Arguments section of the help page, we find the following line:
...: optional arguments to ‘FUN’.
So all you have ...
How to create multiple directories from a single full path in C#?
If you have a full path like: "C:\dir0\dir1\dir2\dir3\dir4\" how would you best implement it so that all directories are present?
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Base64: What is the worst possible increase in space usage?
If a server received a base64 string and wanted to check it's length before converting,, say it wanted to always permit the final byte array to be 16KB. How big could a 16KB byte array possibly become when converted to a Base64 string (assuming one byte per character)?
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How to make a cross-module variable?
The __debug__ variable is handy in part because it affects every module. If I want to create another variable that works the same way, how would I do it?
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Reverting part of a commit with git
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git reset -p # -p is short for --patch
Then commit reverse diff of the bad changes
git commit -m "Partially revert <sha1>..."
Finally the reverted GOOD changes (which have been unstaged by the reset command) are still in the working tree. They need to be cleaned up. If no oth...
AJAX post error : Refused to set unsafe header “Connection”
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What "vulnerability" does Connection: close cause? If you know a request will take a long time, it should be possible to request that it not tie up the persistent connection. Browsers don't support request pipelining either, so if a long running request comes before a normal ...
How to use enums as flags in C++?
...t;(a) | static_cast<int>(b));
}
Etc. rest of the bit operators. Modify as needed if the enum range exceeds int range.
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How to sort strings in JavaScript
.... You may also see the following code used that doesn't respect a locale:
if (item1.attr < item2.attr)
return -1;
if ( item1.attr > item2.attr)
return 1;
return 0;
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Pythonic way to check if a file exists? [duplicate]
Which is the preferred way to check if a file exists and if not create it?
5 Answers
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