65 lines
2.0 KiB
Python
65 lines
2.0 KiB
Python
class Comparable:
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"""Customise how your Enum acts when compared to other objects.
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Your Enum must implement a ``_cmp_values`` method which takes the Enum
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member's value and the other value and manipulates them into the actual
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values that can be compared.
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A case-insensitive StrEnum might look like this::
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class HttpHeader(Comparable, KebabCaseStrEnum):
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ContentType = auto()
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Host = auto()
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Accept = auto()
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XForwardedFor = auto()
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def _cmp_values(self, other):
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return self.value.lower(), str(other).lower()
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You could then use these headers in case-insensitive comparisons::
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assert "Content-Type" == HttpHeader.ContentType
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assert "content-type" == HttpHeader.ContentType
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assert "coNtEnt-tyPe" == HttpHeader.ContentType
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.. note::
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Your ``_cmp_values`` method *must not* return ``self`` as one of the
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values to be compared -- that would result in infinite recursion.
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Instead, perform operations on ``self.value`` and return that.
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.. warning::
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A bug in Python prior to 3.7.1 prevents mix-ins working with Enum
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subclasses.
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.. versionadded:: 0.4.6
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"""
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def __eq__(self, other):
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value, other = self._cmp_values(other)
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return value == other
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def __ne__(self, other):
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value, other = self._cmp_values(other)
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return value != other
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def __lt__(self, other):
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value, other = self._cmp_values(other)
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return value < other
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def __le__(self, other):
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value, other = self._cmp_values(other)
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return value <= other
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def __gt__(self, other):
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value, other = self._cmp_values(other)
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return value > other
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def __ge__(self, other):
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value, other = self._cmp_values(other)
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return value >= other
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def _cmp_values(self, other):
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raise NotImplementedError(
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"Enum's using Comparable must implement their own _cmp_values function."
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)
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