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Can C++ code be valid in both C++03 and C++11 but do different things?

Is it possible for C++ code to conform to both the C++03 standard and the C++11 standard, but do different things depending on under which standard it is being compiled? ...
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Can you test google analytics on a localhost address?

..., however the technology has changed. The old Urchin tracker is deprecated and obsolete. The new asynchronous Google Analytics tracking code uses slightly different code to achieve the same results. Google Analytics Classic - Asynchronous Syntax - ga.js The current syntax for setting the tracking do...
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If strings are immutable in .NET, then why does Substring take O(n) time?

... liked this question so much, I just blogged it. See Strings, immutability and persistence The short answer is: O(n) is O(1) if n does not grow large. Most people extract tiny substrings from tiny strings, so how the complexity grows asymptotically is completely irrelevant. The long answer is: ...
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Why does PHP 5.2+ disallow abstract static class methods?

After enabling strict warnings in PHP 5.2, I saw a load of strict standards warnings from a project that was originally written without strict warnings: ...
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Should I instantiate instance variables on declaration or in the constructor?

...he compiler. The first variant is more readable. You can't have exception handling with the first variant. There is additionally the initialization block, which is as well put in the constructor(s) by the compiler: { a = new A(); } Check Sun's explanation and advice From this tutorial: ...
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Why does C++11 not support designated initializer lists as C99? [closed]

... constructor. This is the sort of abstraction C++ promotes. On the other hand the designated initializers feature is more about exposing and making members easy to access directly in client code. This leads to things like having a person of age 18 (years?) but with height and weight of zero. In ...
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What are the differences between a clustered and a non-clustered index?

What are the differences between a clustered and a non-clustered index ? 12 Answers ...
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What is the MySQL VARCHAR max size?

...ySQL table has a maximum row size limit of 65,535 bytes, not counting BLOB and TEXT types. BLOB and TEXT columns only contribute 9 to 12 bytes toward the row size limit because their contents are stored separately from the rest of the row. Read more about Limits on Table Column Count and Row Size. ...
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Is there any kind of hash code function in JavaScript?

...d, alternatively, maintain an array which indexes the objects in question, and use its index string as a reference to the object. Something like this: var ObjectReference = []; ObjectReference.push(obj); set['ObjectReference.' + ObjectReference.indexOf(obj)] = true; Obviously it's a little verbo...
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Is there a rule-of-thumb for how to divide a dataset into training and validation sets?

Is there a rule-of-thumb for how to best divide data into training and validation sets? Is an even 50/50 split advisable? Or are there clear advantages of having more training data relative to validation data (or vice versa)? Or is this choice pretty much application dependent? ...