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To underscore or to not to underscore, that is the question
...other framework languages? For example since C# is case-sensitive you can call a field "foo" and the public property "Foo" and it works fine.
...
Why is __init__() always called after __new__()?
... new instance.
__new__ is the first step of instance creation. It's called first, and is
responsible for returning a new
instance of your class.
In contrast,
__init__ doesn't return anything; it's only responsible for initializing the
instance after it's been created.
In ge...
String concatenation in Ruby
...ficient in term of memory/speed from what I've seen (not measured though). All three methods will throw an uninitialized constant error when ROOT_DIR is nil.
When dealing with pathnames, you may want to use File.join to avoid messing up with pathname separator.
In the end, it is a matter of taste....
How to reliably open a file in the same directory as a Python script
...th(
os.path.join(os.getcwd(), os.path.dirname(__file__)))
The join() call prepends the current working directory, but the documentation says that if some path is absolute, all other paths left of it are dropped. Therefore, getcwd() is dropped when dirname(__file__) returns an absolute path.
Als...
In which case do you use the JPA @JoinTable annotation?
... project_id
name name task_id
The Project_Tasks table is called a "Join Table". To implement this second solution in JPA you need to use the @JoinTable annotation. For example, in order to implement a uni-directional one-to-many association, we can define our entities as such:
Proj...
Remove secure warnings (_CRT_SECURE_NO_WARNINGS) from projects by default in Visual Studio
Is there a way to set by default for all projects removing the precompiler secure warnings that come up when using functions like scanf(). I found that you can do it by adding a line in the project option or a #define _CRT_SECURE_NO_WARNINGS in the beginning of the code.
...
Multiple glibc libraries on a single host
...d to know that glibc consists of many pieces (200+ shared libraries) which all must match. One of the pieces is ld-linux.so.2, and it must match libc.so.6, or you'll see the errors you are seeing.
The absolute path to ld-linux.so.2 is hard-coded into the executable at link time, and can not be easi...
How to print a query string with parameter values when using Hibernate
...he the following categories:
org.hibernate.SQL - set to debug to log all SQL DML statements as they are executed
org.hibernate.type - set to trace to log all JDBC parameters
So a log4j configuration could look like:
# logs the SQL statements
log4j.logger.org.hibernate.SQL=debug
# Logs the...
What's the bad magic number error?
...the pyc file or trying to run a pyc from a different version of python (usually later) than your interpreter.
If they are your pyc files, just delete them and let the interpreter re-compile the py files. On UNIX type systems, that could be something as simple as:
rm *.pyc
or:
find . -name '*.py...
How are Python's Built In Dictionaries Implemented?
...e).
Python dictionaries are implemented as hash tables.
Hash tables must allow for hash collisions i.e. even if two distinct keys have the same hash value, the table's implementation must have a strategy to insert and retrieve the key and value pairs unambiguously.
Python dict uses open addressin...