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How to achieve function overloading in C?
...sociation list that looks a bit like a switch block. _Generic gets the overall type of the expression and then "switches" on it to select the end result expression in the list for its type:
_Generic(1, float: 2.0,
char *: "2",
int: 2,
default: get_two_object());
...
Static class initializer in PHP
I have an helper class with some static functions. All the functions in the class require a ‘heavy’ initialization function to run once (as if it were a constructor).
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How to create module-wide variables in Python? [duplicate]
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Here is what is going on.
First, the only global variables Python really has are module-scoped variables. You cannot make a variable that is truly global; all you can do is make a variable in a particular scope. (If you make a variable inside the Python interpreter, and then import other mo...
Python (and Python C API): __new__ versus __init__
...vs immutable types.
__new__ accepts a type as the first argument, and (usually) returns a new instance of that type. Thus it is suitable for use with both mutable and immutable types.
__init__ accepts an instance as the first argument and modifies the attributes of that instance. This is inappropr...
What is a clean, pythonic way to have multiple constructors in Python?
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Actually None is much better for "magic" values:
class Cheese():
def __init__(self, num_holes = None):
if num_holes is None:
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Now if you want complete freedom of adding more parameters:
class Cheese...
Get $_POST from multiple checkboxes
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Set the name in the form to check_list[] and you will be able to access all the checkboxes as an array($_POST['check_list'][]).
Here's a little sample as requested:
<form action="test.php" method="post">
<input type="checkbox" name="check_list[]" value="value 1">
<input t...
How to import a module given its name as string?
...mand" modules makes his/her whole command-app fail on one exception. Personally I'd for loop over each import individually wrapped in a try: mods=__import__()\nexcept ImportError as error: report(error) to allow other commands to continue to work while the bad ones get fixed.
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Case insensitive 'in'
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Prefer to lower all keys when building the dict, for performance reasons.
– Ryan
May 1 '13 at 6:27
1
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Why do some functions have underscores “__” before and after the function name?
...rms using leading or trailing underscores are
recognized (these can generally be combined with any case convention):
_single_leading_underscore: weak "internal use" indicator. E.g. from M import * does not import objects whose name starts with an underscore.
single_trailing_underscore_: ...
How do I use prepared statements in SQlite in Android?
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I use prepared statements in Android all the time, it's quite simple :
SQLiteDatabase db = dbHelper.getWritableDatabase();
SQLiteStatement stmt = db.compileStatement("INSERT INTO Country (code) VALUES (?)");
stmt.bindString(1, "US");
stmt.executeInsert();
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