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What do 'real', 'user' and 'sys' mean in the output of time(1)?
...al refers to actual elapsed time; User and Sys refer to CPU time used only by the process.
Real is wall clock time - time from start to finish of the call. This is all elapsed time including time slices used by other processes and time the process spends blocked (for example if it is waiting for ...
Is a statically-typed full Lisp variant possible?
Is a statically-typed full Lisp variant possible? Does it even make sense for something like this to exist? I believe one of a Lisp language's virtues is the simplicity of its definition. Would static typing compromise this core principle?
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HTML5 best practices; section/header/aside/article elements
There is enough information about HTML5 on the web (and also on stackoverflow), but now I'm curious about the "best practices". Tags like section/headers/article are new, and everyone has different opinions about when/where you should use these tags. So what do you guys think of the following layout...
How should one use std::optional?
...the documentation of std::experimental::optional and I have a good idea about what it does, but I don't understand when I should use it or how I should use it. The site doesn't contain any examples as of yet which leaves it harder for me to grasp the true concept of this object. When is std::op...
WiX tricks and tips
We've been using WiX for a while now, and despite the usual gripes about ease of use, it's going reasonably well. What I'm looking for is useful advice regarding:
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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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Hash collision in git
...g atoms on 10 Moons
An SHA-1 hash is a 40 hex character string... that's 4 bits per character times 40... 160 bits. Now we know 10 bits is approximately 1000 (1024 to be exact) meaning that there are 1 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 different SHA-1 hashes... 1048.
Wh...
Why is Git better than Subversion?
I've been using Subversion for a few years and after using SourceSafe , I just love Subversion. Combined with TortoiseSVN , I can't really imagine how it could be any better.
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How do I properly clean up Excel interop objects?
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Excel does not quit because your application is still holding references to COM objects.
I guess you're invoking at least one member of a COM object without assigning it to a variable.
For me it was the excelApp.Worksheets object which I direc...
Optimise PostgreSQL for fast testing
...on of PostgreSQL. Performance improvements are always coming, so you're probably wasting your time if you're tuning an old version. For example, PostgreSQL 9.2 significantly improves the speed of TRUNCATE and of course adds index-only scans. Even minor releases should always be followed; see the ver...