Memory efficient Python objects
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mrakitin and MatthieuDartiailh FIX: proper size check for list creation (#79)
was FIX: fix SIZE_MAX error for Linux/Python 3.6
Latest commit 7fb3267 May 15, 2018


Welcome to Atom

Atom is a framework for creating memory efficient Python objects with enhanced features such as dynamic initialization, validation, and change notification for object attributes. It provides the default model binding behaviour for the Enaml UI framework.

Illustrative Example:

from atom.api import Atom, Unicode, Range, Bool, observe

class Person(Atom):
    """ A simple class representing a person object.

    last_name = Unicode()

    first_name = Unicode()

    age = Range(low=0)

    debug = Bool(False)

    def debug_print(self, change):
        """ Prints out a debug message whenever the person's age changes.

        if self.debug:
            templ = "{first} {last} is {age} years old."
            s = templ.format(
                first=self.first_name, last=self.last_name, age=self.age,

    def _default_first_name(self):
        return 'John'

john = Person(last_name='Doe', age=42)
john.debug = True
john.age = 43  # prints message
john.age = 'forty three'   # raises TypeError

For version information, see the Revision History.