Class Length

src/docx/shared.py:25–70

Base class for length constructor classes Inches, Cm, Mm, Px, and Emu. Behaves as an int count of English Metric Units, 914,400 to the inch, 36,000 to the mm. Provides convenience unit conversion methods in the form of read-only properties. Immutable.

class Length(int):
    """Base class for length constructor classes Inches, Cm, Mm, Px, and Emu.

    Behaves as an int count of English Metric Units, 914,400 to the inch, 36,000 to the
    mm. Provides convenience unit conversion methods in the form of read-only
    properties. Immutable.
    """

    _EMUS_PER_INCH = 914400
    _EMUS_PER_CM = 360000
    _EMUS_PER_MM = 36000
    _EMUS_PER_PT = 12700
    _EMUS_PER_TWIP = 635

    def __new__(cls, emu: int):
        return int.__new__(cls, emu)

    @property
    def cm(self):
        """The equivalent length expressed in centimeters (float)."""
        return self / float(self._EMUS_PER_CM)

    @property
    def emu(self):
        """The equivalent length expressed in English Metric Units (int)."""
        return self

    @property
    def inches(self):
        """The equivalent length expressed in inches (float)."""
        return self / float(self._EMUS_PER_INCH)

    @property
    def mm(self):
        """The equivalent length expressed in millimeters (float)."""
        return self / float(self._EMUS_PER_MM)

    @property
    def pt(self):
        """Floating point length in points."""
        return self / float(self._EMUS_PER_PT)

    @property
    def twips(self):
        """The equivalent length expressed in twips (int)."""
        return int(round(self / float(self._EMUS_PER_TWIP)))


class Inches(Length):