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Python argparse: How to insert newline in the help text?
I'm using argparse in Python 2.7 for parsing input options. One of my options is a multiple choice. I want to make a list in its help text, e.g.
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Conditional compilation and framework targets
There are a few minor places where code for my project may be able to be drastically improved if the target framework were a newer version. I'd like to be able to better leverage conditional compilation in C# to switch these as needed.
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Understanding slice notation
...d
Python is kind to the programmer if there are fewer items than you ask for. For example, if you ask for a[:-2] and a only contains one element, you get an empty list instead of an error. Sometimes you would prefer the error, so you have to be aware that this may happen.
Relation to slice() obje...
Getter and Setter declaration in .NET [duplicate]
...y, you can encapsulate the way your data is accessed. C# has a nice syntax for turning a field into a property:
string MyProperty { get; set; }
This is called an auto-implemented property. When the need arises you can expand your property to:
string _myProperty;
public string MyProperty
{
g...
What are 'get' and 'set' in Swift?
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That's actually explained right before the code:
In addition to simple properties that are stored, properties can have a getter and a setter.
class EquilateralTriangle: NamedShape {
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When some other class wants to get that perimeter variable, they ...
static constructors in C++? I need to initialize private static objects
...-z). In java or C#, I can just make a "static constructor" that will run before I make any instances of the class, and sets up the static data members of the class. It only gets run once (as the variables are read only and only need to be set once) and since it's a function of the class it can acces...
Objective-C declared @property attributes (nonatomic, copy, strong, weak)
...must use each attribute: nonatomic , copy , strong , weak , and so on, for a declared property, and explain what each does? Some sort of example would be great also. I am using ARC.
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What is a proper naming convention for MySQL FKs?
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In MySQL, there is no need to give a symbolic name to foreign key constraints. If a name is not given, InnoDB creates a unique name automatically.
In any case, this is the convention that I use:
fk_[referencing table name]_[referenced table name]_[referencing field name]
Exa...
Unzip a file with php
...ect way to unzip a file is a bit frightening.
PHP has built-in extensions for dealing with compressed files. There should be no need to use system calls for this. ZipArchivedocs is one option.
$zip = new ZipArchive;
$res = $zip->open('file.zip');
if ($res === TRUE) {
$zip->extractTo('/myzi...
Log exception with traceback
... except: handler/block to log the current exception along with the trace information, prepended with a message.
import logging
LOG_FILENAME = '/tmp/logging_example.out'
logging.basicConfig(filename=LOG_FILENAME, level=logging.DEBUG)
logging.debug('This message should go to the log file')
try:
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