music21.common.enums

AppendSpanners

class music21.common.enums.AppendSpanners(value, names=<not given>, *values, module=None, qualname=None, type=None, start=1, boundary=None)

An enumeration for how to append related spanners when appending objects to a written file.

AppendSpanners.NORMAL means append the spanners that start with the object, then append

the object, then append the spanners that end with the object.

AppendSpanners.RELATED_ONLY means append the spanners that start with the object, then

append the spanners that end with the object (i.e. do not append the object).

AppendSpanners.NONE means do not append the related spanners at all (i.e. only append

the object).

  • new in v9.

AppendSpanners bases

BooleanEnum

class music21.common.enums.BooleanEnum(value, names=<not given>, *values, module=None, qualname=None, type=None, start=1, boundary=None)

An enum that replaces a boolean, except the “is” part, and allows specifying multiple values that can specify whether they equate to True or False.

Useful for taking an element that was previously True/False and replacing it in a backwards-compatible way with an Enum.

>>> from music21.common.enums import BooleanEnum
>>> class Maybe(BooleanEnum):
...    YES = True
...    NO = False
...    MAYBE = 0.5
...    NOT_A_CHANCE = (False, 'not a chance')
...    DEFINITELY = (True, 'of course!')
>>> bool(Maybe.YES)
True
>>> bool(Maybe.NO)
False
>>> bool(Maybe.MAYBE)
True
>>> bool(Maybe.NOT_A_CHANCE)
False
>>> bool(Maybe.DEFINITELY)
True
>>> Maybe.MAYBE == 0.5
True
>>> Maybe.NOT_A_CHANCE == 'not a chance'
True
>>> Maybe.NOT_A_CHANCE == False
True
>>> Maybe.NOT_A_CHANCE == True
False
>>> Maybe.NOT_A_CHANCE == 'not any chance'
False
>>> Maybe.DEFINITELY == 'of course!'
True
>>> Maybe.NOT_A_CHANCE == (False, 'not a chance')
True

ContainsEnum

class music21.common.enums.ContainsEnum(value, names=<not given>, *values, module=None, qualname=None, type=None, start=1, boundary=None)

An IntEnum that allows “in” checks against the values of the enum.

ContainsMeta

class music21.common.enums.ContainsMeta(cls, bases, classdict, *, boundary=None, _simple=False, **kwds)

This is a backport of the Python 3.12 EnumType class’s contains method.

ElementSearch

class music21.common.enums.ElementSearch(value, names=<not given>, *values, module=None, qualname=None, type=None, start=1, boundary=None)

An enum representing the element search directions that can be provided to getContextByClass().

ElementSearch bases

GatherSpanners

class music21.common.enums.GatherSpanners(value, names=<not given>, *values, module=None, qualname=None, type=None, start=1, boundary=None)

An enumeration for how to gather missing spanners

>>> from music21.common.enums import GatherSpanners

Indicates all relevant spanners will be gathered:

>>> GatherSpanners.ALL
<GatherSpanners.ALL>
>>> bool(GatherSpanners.ALL)
True

Indicates no relevant spanners will be gathered:

>>> GatherSpanners.NONE
<GatherSpanners.NONE>
>>> bool(GatherSpanners.NONE)
False

Indicates only spanners where all of their members are in the excerpt will be gathered:

>>> GatherSpanners.COMPLETE_ONLY
<GatherSpanners.COMPLETE_ONLY>
>>> bool(GatherSpanners.COMPLETE_ONLY)
True

GatherSpanners bases

MeterDivision

class music21.common.enums.MeterDivision(value, names=<not given>, *values, module=None, qualname=None, type=None, start=1, boundary=None)

Represents an indication of how to divide a TimeSignature

  • New in v7.

MeterDivision bases

OffsetSpecial

class music21.common.enums.OffsetSpecial(value, names=<not given>, *values, module=None, qualname=None, type=None, start=1, boundary=None)

An enum that represents special offsets.

The enum AT_END is equal to the string ‘highestTime’

>>> from music21.common.enums import OffsetSpecial
>>> OffsetSpecial.AT_END
<OffsetSpecial.AT_END>
>>> 'highestTime' == OffsetSpecial.AT_END
True
>>> 'crazyOffset' in OffsetSpecial
False
>>> 6.0 in OffsetSpecial
False
>>> 'lowestOffset' in OffsetSpecial
True
>>> str(OffsetSpecial.AT_END)
'highestTime'

  • New in v7.

  • Note – a previous note said that the ‘highestTime’ == OffsetSpecial.AT_END would be removed in v9 or an upcoming music21 release. Since then, Python has changed direction and in 3.11 added StrEnum to the standard library and in 3.12 allows for containment checks of strings in StrEnum (such as ‘lowestOffset’ in OffsetSpecial returning True). Therefore there is no reason for music21 to ever remove this valuable and backwards compatible tool.

OffsetSpecial bases

OrnamentDelay

class music21.common.enums.OrnamentDelay(value, names=<not given>, *values, module=None, qualname=None, type=None, start=1, boundary=None)

An enumeration for the delay in an ornament (e.g. a delayed turn). The delay for an ornament can be set to one of these values, or to an OffsetQL for a timed delay.

OrnamentDelay.NO_DELAY means there is no delay (this is equivalent to setting delay to 0.0) OrnamentDelay.DEFAULT_DELAY means the delay is half the duration of the ornamented note.

  • new in v9.

OrnamentDelay bases

StrEnum

class music21.common.enums.StrEnum(value, names=<not given>, *values, module=None, qualname=None, type=None, start=1, boundary=None)

An enumeration where strings can equal the value, and strings can be found “in” the enum.

See music21.common.enums.OffsetSpecial for an example of how subclassing this would work.

  • Note: This class predates the equivalent StrEnum in Python 3.11 and the changes to Enum __contains__ in 3.12. Once Python 3.12 is the minimum version of music21, this class will no longer be used internally and will eventually become deprecated (2027?) and removed (2030?).

StrEnumMeta

class music21.common.enums.StrEnumMeta(cls, bases, classdict, *, boundary=None, _simple=False, **kwds)