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Performance - Date.now() vs Date.getTime()
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These things are the same (edit semantically; performance is a little better with .now()):
var t1 = Date.now();
var t2 = new Date().getTime();
However, the time value from any already-created Date instance is frozen at the time of its construction (or at whateve...
Can you add new statements to Python's syntax?
... a hands-on approach here: I'm going to add an until statement to Python.
All the coding for this article was done against the cutting-edge Py3k branch in the Python Mercurial repository mirror.
The until statement
Some languages, like Ruby, have an until statement, which is the complement to whi...
Can anybody find the TFS “Unshelve” option in Visual Studio 2012?
..."Find Shelvesets", then right click on the shelve you want to unshelve, finally "Unshelve".
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Commit changes to a different branch than the currently checked out branch with subversion
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I recommend not to choose the root folder with all the irrelevant sub-folders which are not subject to be modified in the branch. Later it will be easier to merge the (smaller) branch back to trunk.
– J Pollack
Mar 5 '15 at 9:24
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How to manually deprecate members
...ike Objective-C, Swift has no preprocessor, so is there still a way to manually deprecate members of a class?
4 Answers
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In C#, how can I create a TextReader object from a string (without writing to disk)
...text into a webpage. The Fast CSV reader requires a TextReader object, and all I have is a string. What's the best way to convert a string into a TextReader object on the fly?
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SELECT * WHERE NOT EXISTS
...r original query will always return nothing unless there are no records at all in eotm_dyn, in which case it will return everything.
Assuming these tables should be joined on employeeID, use the following:
SELECT *
FROM employees e
WHERE NOT EXISTS
(
SELECT null
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What is the way to quick-switch between tabs in Xcode 4
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I think everybody should assume that people are generally used to browser ~ and use CTR + TAB / CTR + SHIFT + TAB to change tabs.
– Paul Brewczynski
Aug 19 '13 at 14:27
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Using :after to clear floating elements
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The text 'dasda' will never not be within a tag, right? Semantically and to be valid HTML it as to be, just add the clear class to that:
http://jsfiddle.net/EyNnk/2/
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Pass a data.frame column name to a function
...l_name,col1,col2){
df$col_name <- df$col1 + df$col2
df
}
#Call foo() like this:
foo(dat,z,x,y)
The problem here is that df$col1 doesn't evaluate the expression col1. It simply looks for a column in df literally called col1. This behavior is described in ?Extract under the secti...