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Why is TypedReference behind the scenes? It's so fast and safe… almost magical!

... Short answer: portability. While __arglist, __makeref, and __refvalue are language extensions and are undocumented in the C# Language Specification, the constructs used to implement them under the hood (vararg calling convention, TypedReference type, arglist, refanytype, mkanyref...
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In Python, what is the difference between “.append()” and “+= []”?

...d will add one item to the list, while += will copy all elements of right-hand-side list into the left-hand-side list. Update: perf analysis Comparing bytecodes we can assume that append version wastes cycles in LOAD_ATTR + CALL_FUNCTION, and += version -- in BUILD_LIST. Apparently BUILD_LIST outw...
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&& (AND) and || (OR) in IF statements

... No, it will not be evaluated. And this is very useful. For example, if you need to test whether a String is not null or empty, you can write: if (str != null && !str.isEmpty()) { doSomethingWith(str.charAt(0)); } or, the other way around if ...
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“CAUTION: provisional headers are shown” in Chrome debugger

...r Latest Versions of chrome Type chrome://net-export/ in the address bar and hit enter. Start Recording. And save Recording file to local. Open the page that is showing problems. Go back to net-internals You can view Recorded Log file Here https://netlog-viewer.appspot.com/#import click on events ...
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How to define a two-dimensional array?

...sion that could arise with the indexing, if you use "x" for both the inner and outer lists, and want a non-square Matrix. share | improve this answer | follow ...
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How do you remove duplicates from a list whilst preserving order?

...o seen_add instead of just calling seen.add? Python is a dynamic language, and resolving seen.add each iteration is more costly than resolving a local variable. seen.add could have changed between iterations, and the runtime isn't smart enough to rule that out. To play it safe, it has to check the o...
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Singleton pattern in nodejs - is it needed?

... This has basically to do with nodejs caching. Plain and simple. https://nodejs.org/api/modules.html#modules_caching (v 6.3.1) Caching Modules are cached after the first time they are loaded. This means (among other things) that every call to require('foo') will ge...
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Flexbox: center horizontally and vertically

How to center div horizontally, and vertically within the container using flexbox. In below example, I want each number below each other (in rows), which are centered horizontally. ...
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Git ignore sub folders

...t of projects in my .Net solution. I would like to exclude all "bin/Debug" and "bin/Release" folders (and their contents), but still include the "bin" folder itself and any dll's contained therein. ...
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Is it possible to use argsort in descending order?

... If you negate an array, the lowest elements become the highest elements and vice-versa. Therefore, the indices of the n highest elements are: (-avgDists).argsort()[:n] Another way to reason about this, as mentioned in the comments, is to observe that the big elements are coming last in the ar...