Python has no privacy model, there are no access modifiers like in C++, C# or Java. There are no truly ‘protected’ or ‘private’ attributes. Names with a leading double underscore and no trailing double underscore are mangled to protect them from clashes when inherited. Subclasses can define their own __private() method and these will not … Read more
The answer, in a few words In your example, itsProblem is a local variable. Your must use self to set and get instance variables. You can set it in the __init__ method. Then your code would be: class Example(object): def __init__(self): self.itsProblem = “problem” theExample = Example() print(theExample.itsProblem) But if you want a true class … Read more
array_unique works with an array of objects using SORT_REGULAR: class MyClass { public $prop; } $foo = new MyClass(); $foo->prop = ‘test1’; $bar = $foo; $bam = new MyClass(); $bam->prop = ‘test2’; $test = array($foo, $bar, $bam); print_r(array_unique($test, SORT_REGULAR)); Will print: Array ( [0] => MyClass Object ( [prop] => test1 ) [2] => MyClass … Read more
Since you’re referring to instance variables, I’m assuming that you’re working in an object-oriented language. To some degree, when to use instance variables, how to define their scope, and when to use local variables is subjective, but there are a couple of rules of thumb you can follow whenever creating your classes. Instance variables are … Read more
Xcode allows you to (un)check settings for specific compiler warnings that can warn you of some types of unused code. (Select the project in the source list and File > Get Info, then select the Build tab.) Here are a few (which show up for Clang and GCC 4.2 for me) which may be of … Read more
The way you describe it is absolutely not possible. Assignment to a name is a fundamental feature of Python and no hooks have been provided to change its behavior. However, assignment to a member in a class instance can be controlled as you want, by overriding .__setattr__(). class MyClass(object): def __init__(self, x): self.x = x … Read more
It seems to me that it’s mostly a matter of style: I strongly prefer using properties for just that: properties; meaning simple values that you can get and/or set. I use functions (or methods) when actual work is being done. Maybe something has to be computed or read from disk or from a database: In … Read more
It depends. There are really 2 types of static methods: Methods that are static because they CAN be Methods that are static because they HAVE to be In a small to medium size code base you can really treat the two methods interchangeably. If you have a method that is in the first category (can-be-static), … Read more
You can harness __call for this: class Foo { public function __call($method, $args) { if (isset($this->$method)) { $func = $this->$method; return call_user_func_array($func, $args); } } } $foo = new Foo(); $foo->bar = function () { echo “Hello, this function is added at runtime”; }; $foo->bar();
It’s “just sugarcoating” for readability, but they do have common meanings: Methods ending in ! perform some permanent or potentially dangerous change; for example: Enumerable#sort returns a sorted version of the object while Enumerable#sort! sorts it in place. In Rails, ActiveRecord::Base#save returns false if saving failed, while ActiveRecord::Base#save! raises an exception. Kernel::exit causes a script … Read more