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What is the exact meaning of IFS=$'\n'?
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Normally bash doesn't interpret escape sequences in string literals. So if you write \n or "\n" or '\n', that's not a linebreak - it's the letter n (in the first case) or a backslash followed by the letter n (in the other two cas...
Can a class member function template be virtual?
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Templates are all about the compiler generating code at compile-time. Virtual functions are all about the run-time system figuring out which function to call at run-time.
Once the run-time system figured out it would need to call a templ...
Manipulating an Access database from Java without ODBC
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UCanAccess is a pure Java JDBC driver that allows us to read from and write to Access databases without using ODBC. It uses two other packages, Jackcess and HSQLDB, to perform these tasks. The following is a brief overview of how to get it set up.
Option 1: Using...
How do PHP sessions work? (not “how are they used?”)
Session files are usually stored in, say, /tmp/ on the server, and named sess_{session_id} . I have been looking at the contents and cannot figure out how they really work.
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When is a C++ destructor called?
Basic Question: when does a program call a class' destructor method in C++? I have been told that it is called whenever an object goes out of scope or is subjected to a delete
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How is a CRC32 checksum calculated?
... 1 0000 0100 1100 0001 0001 1101 1011 0111
The highest term (x32) is usually not explicitly written, so it can instead be represented in hex just as
0x 04 C1 1D B7
Feel free to count the 1s and 0s, but you'll find they match up with the polynomial, where 1 is bit 0 (or the first bit) and x ...
How to change the author and committer name and e-mail of multiple commits in Git?
...ch the docs now give this warning:
git filter-branch has a plethora of pitfalls that can produce non-obvious manglings of the intended history rewrite (and can leave you with little time to investigate such problems since it has such abysmal performance). These safety and performance issues cannot b...
List of Big-O for PHP functions
After using PHP for a while now, I've noticed that not all built-in PHP functions are as fast as expected. Consider these two possible implementations of a function that finds if a number is prime using a cached array of primes.
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What Makes a Good Unit Test? [closed]
...ng lots of automated tests and that you also have run into some common pitfalls when unit testing.
18 Answers
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SQLAlchemy - Getting a list of tables
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All of the tables are collected in the tables attribute of the SQLAlchemy MetaData object. To get a list of the names of those tables:
>>> metadata.tables.keys()
['posts', 'comments', 'users']
If you're using the...