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How can I easily view the contents of a datatable or dataview in the immediate window
Sometimes I will be at a breakpoint in my code and I want to view the contents of a DataTable variable (or a DataTable in a DataSet ). The quick watch doesn't give you a very clear view of the contents. How can I view them easily?
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javascript set a variable if undefined
I know that I can test for a javascript variable and then define it if it is undefined, but is there not some way of saying
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How to optimize for-comprehensions and loops in Scala?
...imizer can eliminate the foreach but cannot yet eliminate the throw/catch. And throw/catch is expensive. But since such nested returns are rare in Scala programs, the optimizer did not yet address this case. There is work going on to improve the optimizer which hopefully will solve this issue soon.
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Which, if any, C++ compilers do tail-recursion optimization?
...t it would work perfectly well to do tail-recursion optimization in both C and C++, yet while debugging I never seem to see a frame stack that indicates this optimization. That is kind of good, because the stack tells me how deep the recursion is. However, the optimization would be kind of nice as w...
How do I interpret precision and scale of a number in a database?
...rget that if you're using a system that allows you to pre-define precision and scale of an input for a percentage in something like Microsoft Access, you must consider the percent as it's whole number form. In this case, 25.5% would require precision 4 and scale of 3 (not one) since we have to cons...
C# Thread safe fast(est) counter
...ment will have better performance than lock(). Just take a look at the IL and Assembly where you will see that Increment turns into a "bus lock" statement and its variable is directly incremented (x86) or "added" to (x64).
This "bus lock" statement locks the bus to prevent another CPU from acces...
Format output string, right alignment
...ew = '{:>12} {:>12} {:>12}'.format(word[0], word[1], word[2])
And here's how to do it using the old % syntax (useful for older versions of Python that don't support str.format):
line_new = '%12s %12s %12s' % (word[0], word[1], word[2])
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html5 - canvas element - Multiple layers
...ver, you could layer multiple <canvas> elements on top of each other and accomplish something similar.
<div style="position: relative;">
<canvas id="layer1" width="100" height="100"
style="position: absolute; left: 0; top: 0; z-index: 0;"></canvas>
<canvas id="layer...
Stacked Tabs in Bootstrap 3
...
Left, Right and Below tabs were removed from Bootstrap 3, but you can add custom CSS to achieve this..
.tabs-below > .nav-tabs,
.tabs-right > .nav-tabs,
.tabs-left > .nav-tabs {
border-bottom: 0;
}
.tab-content > .tab-pan...
nil detection in Go
...mpiler is pointing the error to you, you're comparing a structure instance and nil. They're not of the same type so it considers it as an invalid comparison and yells at you.
What you want to do here is to compare a pointer to your config instance to nil, which is a valid comparison. To do that you...