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Does Python have a package/module management system?
Does Python have a package/module management system, similar to how Ruby has rubygems where you can do gem install packagename ?
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Why would anyone use set instead of unordered_set?
C++0x is introducing unordered_set which is available in boost and many other places. What I understand is that unordered_set is hash table with O(1) lookup complexity. On the other hand, set is nothing but a tree with log(n) lookup complexity. Why on earth would anyone use set instead ...
How to set auto increment primary key in PostgreSQL?
I have a table in PostgreSQL with 22 columns, and I want to add an auto increment primary key.
7 Answers
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What's the difference between django OneToOneField and ForeignKey?
What's the difference between Django OneToOneField and ForeignKey ?
9 Answers
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Recursive lambda functions in C++11
I am new to C++11. I am writing the following recursive lambda function, but it doesn't compile.
14 Answers
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Any reason not to use '+' to concatenate two strings?
A common antipattern in Python is to concatenate a sequence of strings using + in a loop. This is bad because the Python interpreter has to create a new string object for each iteration, and it ends up taking quadratic time. (Recent versions of CPython can apparently optimize this in some cases, b...
How to override toString() properly in Java?
Sounds a little stupid, but I need help on my toString() method and it is very irking.
I tried looking up online because the toString is the one where it is screwing up and "not finding Kid constructor #2" even though it is there and I would even do something else and it doesn't work.
Ok that w...
PSQLException: current transaction is aborted, commands ignored until end of transaction block
I am seeing the following (truncated) stacktrace in the server.log file of JBoss 7.1.1 Final:
20 Answers
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Studies on optimal code width?
If you enable the "View Right Margin" in your IDE of choice, it is likely that it will default to 80 characters. I tend to change it to 120 for no reason other than it was the standard at a company I was with a few years back, and no other company has told me to do it differently.
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How can I convert a string to a number in Perl?
I have a string which holds a decimal value in it and I need to convert that string into a floating point variable. So an example of the string I have is "5.45" and I want a floating point equivalent so I can add .1 to it. I have searched around the internet, but I only see how to convert a string t...