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Virtual functions and performance - C++

...e a very slight effect on performance, but it's unlikely to affect the overall performance of your application. Better places to look for performance improvements are in algorithms and I/O. An excellent article that talks about virtual functions (and more) is Member Function Pointers and the Fastes...
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How does this JavaScript/jQuery syntax work: (function( window, undefined ) { })(window)?

...d = "new value";. So jQuery creates a local "undefined" variable that is REALLY undefined. The window variable is made local for performance reasons. Because when JavaScript looks up a variable, it first goes through the local variables until it finds the variable name. When it's not found, JavaScr...
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Correct way to write loops for promise.

How to correctly construct a loop to make sure the following promise call and the chained logger.log(res) runs synchronously through iteration? (bluebird) ...
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Difference between 'self' and 'total' in Chrome CPU Profile of JS

...otal is how much time was spent in that function, and in the functions it called. share | improve this answer | follow | ...
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Function overloading by return type?

Why don't more mainstream statically typed languages support function/method overloading by return type? I can't think of any that do. It seems no less useful or reasonable than supporting overload by parameter type. How come it's so much less popular? ...
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quick random row selection in Postgres

... make It sense to use a N less than SELECT COUNT(*)?, I mean, not use all the values in the table but only a part of them? – Juan Mar 14 '11 at 11:00 ...
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Best practices for overriding isEqual: and hash

...ly attributed to Dan Bernstein or Chris Torek. That older algorithm originally floated around on Usenet, and certain attribution is difficult. For example, there is some interesting commentary in this Apache code (search for their names) that references the original source. Bottom line is, this i...
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Why use Dijkstra's Algorithm if Breadth First Search (BFS) can do the same thing faster?

... Dijkstra allows assigning distances other than 1 for each step. For example, in routing the distances (or weights) could be assigned by speed, cost, preference, etc. The algorithm then gives you the shortest path from your source to e...
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Any reason not to start using the HTML 5 doctype? [closed]

... Well consider this: When serving as text/html, all you need a doctype for is to trigger standards mode. Beyond that, the doctype does nothing as far as browsers are concerned. When serving as text/html, whether you use XHTML markup or HTML markup, it's treated by browser...
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How do you find the disk size of a Postgres / PostgreSQL table and its indexes

... and index size in terms of bytes/MB/GB/etc , or even better the size for all tables. In Oracle I had a nasty long query that looked at user_lobs and user_segments to give back an answer. ...