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0 pointspansa24mo ago0 comments

You could also use a normal class, a direct translation of the Ruby example:

    @functools.total_ordering
    class AppVersion:
      def __init__(self, version_string):
        parts = [int(x) for x in str(version_string).split('.')]
        self.major, self.minor, self.patch = parts[0] or 0, parts[1] or 0, parts[2] or 0

      def __lt__(self, other):
        return [self.major, self.minor, self.patch] < [other.major, other.minor, other.patch]

      def __eq__(self, other):
        return [self.major, self.minor, self.patch] == [other.major, other.minor, other.patch]

      def __str__(self):
        return f'{self.major}.{self.minor}.{self.patch}'

0 comments

js24mo ago

FWIW, these lines are not equivalent:

    @major, @minor, @patch = parts[0] || 0, parts[1] || 0, parts[2] || 0

    self.major, self.minor, self.patch = parts[0] or 0, parts[1] or 0, parts[2] or 0

The Ruby case is intended to handle strings like "1", "1.2", and "1.2.3".

The Python code will throw an IndexError as written. Which is why I did this in the namedtuple example:

    parts = [int(x) for x in version_string.split(".")] + [0, 0]

That ensures you'll have at least three parts so you can then:

    self.major, self.minor, self.patch = parts[:3]

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