How do you create a global class in python?

i beg to differ with the view that you can't create something truly global in python. in fact, it is easy. in Python 3.1, it looks like this:

def get_builtins[]:
  """Due to the way Python works, ``__builtins__`` can strangely be either a module or a dictionary,
  depending on whether the file is executed directly or as an import. I couldn’t care less about this
  detail, so here is a method that simply returns the namespace as a dictionary."""
  return getattr[ __builtins__, '__dict__', __builtins__ ]

like a bunch of other things, builtins are one point where Py3 differs in details from the way it used to work in Py2. read the "What's New in Python X.X" documents on python.org for details. i have no idea what the reason for the convention mentioned above might be; i just want to ignore that stuff. i think that above code should work in Py2 as well.

so the point here is there is a __builtins__ thingie which holds a lot of stuff that comes as, well, built-into Python. all the sum, max, range stuff you've come to love. well, almost everything. but you don't need the details, really. the simplest thing you could do is to say

G          = get_builtins[]
G[ 'G' ]   = G
G[ 'axe' ] = axe

at a point in your code that is always guaranteed to execute. G stands in for the globally available namespace, and since i've registered G itself within G, G now magically transcends its existence into the background of every module. means you should use it with care. where naming collisions occur between whatever is held in G and in a module's namespace, the module's namespace should win [as it gets inspected first]. also, be prepared for everybody to jump on you when you tell them you're POLLUTING THE GLOBAL NAMESPACE dammit. i'm relly surprised noone has copmplained about that as yet, here.

well, those people would be quite right, in a way. personally, however, this is one of my main application composition techniques: what you do is you take a step away from the all-purpose module [which shouldn't do such a thing] towards a fine-tuned application-specific namespace. your modules are bound not to work outside that namespace, but then they're not supposed to, either. i actually started this style of programming as an experimental rebellion against [1] established views, hah!, and [2] the desperation that befalls me whenever i want to accomplish something less than trivial using Python's import statement. these days, i only use import for standard library stuff and regularly-installed modules; for my own stuff, i use a homegrown system. what can i say, it works!

ah yes, two more points: do yourself a favor, if you like this solution, and write yourself a publish[] method or the like that oversees you never publish a name that has already been taken. in most cases, you do not want that.

lastly, let me second the first commenter: i have been programming in exactly the style you show above, coz that's what you find in the textbook examples [most of the time using cars, not axes to be sure]. for a rather substantial number of reasons, i've pretty much given up on that.

consider this: JSON defines but seven kinds of data: null, true, false, numbers, texts, lists, dictionaries, that's it. i claim you can model any other useful datatype with those.

there is still a lot of justification for things like sets, bags, ordered dictionaries and so on. the claim here is not that it is always convenient or appropriate to fall back on a pure, directly JSON-compatible form; the claim is only that it is possible to simulate. right now, i'm implementing a sparse list for use in a messaging system, and that data type i do implement in classical OOP. that's what it's good for.

but i never define classes that go beyond these generic datatypes. rather, i write libraries that take generic datatypes and that provide the functionality you need. all of my business data [in your case probably representations of players, scenes, implements and so on] go into generic data container [as a rule, mostly dicts]. i know there are open questions with this way of architecturing things, but programming has become ever so much easier, so much more fluent since i broke thru the BS that part of OOP propaganda is [apart from the really useful and nice things that another part of OOP is].

oh yes, and did i mention that as long as you keep your business data in JSON-compatible objects you can always write them to and resurrect them from the disk? or send them over the wire so you can interact with remote players? and how incredibly twisted the serialization business can become in classical OOP if you want to do that [read this for the tip of the iceberg]? most of the technical detail you have to know in this field is completely meaningless for the rest of your life.

How do you declare a class global in Python?

We declare a variable global by using the keyword global before a variable. All variables have the scope of the block, where they are declared and defined in. They can only be used after the point of their declaration.

How do you create a global module in Python?

How to create a Global Variable.
Create a Global module. #global.py current_value=0..
Create a Python program file to access global variable. #updater.py import global def update_value[]: global.current_value = 100..
Create another Python program to test value is changed or not..

How do you declare a global object in Python?

A global variable in Python is often declared as the top of the program. In other words, variables that are declared outside of a function are known as global variables. You can access global variables in Python both inside and outside the function. Def fn1[]:

How do you declare a global list in Python?

You can declare Global list on the file/module level like: my_global_list = list[] in Python. If you want to append to it inside a function you can use the global keyword.

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