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# Representations of Values

Python's strings, byte strings, integers, booleans, and double-precision floats stand directly for their Preserves counterparts. Wrapper objects for Float and Symbol complete the suite of atomic types.

Python's lists and tuples correspond to Preserves `Sequence`s, and dicts and sets to `Dictionary` and `Set` values, respectively. Preserves `Record`s are represented by Record objects. Finally, embedded values are represented by Embedded objects.

The preserves.values module implements the core representations of Preserves `Value`s as Python values.

## `Annotated(item)`

Bases: `object`

A Preserves `Value` along with a sequence of `Value`s annotating it. Compares equal to the underlying `Value`, ignoring the annotations. See the specification document for more about annotations.

    >>> import preserves
    >>> a = preserves.parse('''
    ... ; A comment
    ... [1 2 3]
    ... ''', include_annotations=True)
    >>> a
    @' A comment' (1, 2, 3)
    >>> a.item
    (1, 2, 3)
    >>> a.annotations
    [' A comment']
    >>> a == (1, 2, 3)
    True
    >>> a == preserves.parse('@xyz [1 2 3]', include_annotations=True)
    True
    >>> a[0]
    Traceback (most recent call last):
      ...
    TypeError: 'Annotated' object is not subscriptable
    >>> a.item[0]
    1
    >>> type(a.item[0])
    <class 'preserves.values.Annotated'>
    >>> a.item[0].annotations
    []
    >>> print(preserves.stringify(a))
    @" A comment" [1 2 3]
    >>> print(preserves.stringify(a, include_annotations=False))
    [1 2 3]

Attributes:

Name | Type | Description
--- | --- | ---
`item` | `Value` | the underlying annotated `Value`
`annotations` | `list[Value]` | the annotations attached to `self.item`

Source code in `preserves/values.py`

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    def __init__(self, item):
        self.annotations = []
        self.item = item

### `peel()`

Calls strip_annotations on `self` with `depth=1`.

Source code in `preserves/values.py`

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    def peel(self):
        """Calls [strip_annotations][preserves.values.strip_annotations] on `self` with `depth=1`."""
        return strip_annotations(self, 1)

### `strip(depth=inf)`

Calls strip_annotations on `self` and `depth`.

Source code in `preserves/values.py`

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    def strip(self, depth=inf):
        """Calls [strip_annotations][preserves.values.strip_annotations] on `self` and `depth`."""
        return strip_annotations(self, depth)

## `Embedded(embeddedValue)`

Representation of a Preserves `Embedded` value. For more on the meaning and use of embedded values, see the specification.

    >>> import io
    >>> e = Embedded(io.StringIO('some text'))
    >>> e                                        # doctest: +ELLIPSIS
    #!<_io.StringIO object at ...>
    >>> e.embeddedValue                          # doctest: +ELLIPSIS
    <_io.StringIO object at ...>

    >>> import preserves
    >>> print(preserves.stringify(Embedded(None)))
    Traceback (most recent call last):
      ...
    TypeError: Cannot preserves-format: None
    >>> print(preserves.stringify(Embedded(None), format_embedded=lambda x: 'abcdef'))
    #!"abcdef"

Attributes:

Name | Type | Description
--- | --- | ---
`embeddedValue` |  | any Python value; could be a platform object, could be a representation of a Preserves `Value`, could be `None`, could be anything!

Source code in `preserves/values.py`

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    def __init__(self, embeddedValue):
        self.embeddedValue = embeddedValue

## `Float(value)`

Bases: `object`

Wrapper for treating a Python double-precision floating-point value as a single-precision (32-bit) float, from Preserves' perspective. (Python lacks native single-precision floating point support.)

    >>> Float(3.45)
    Float(3.45)
    >>> import preserves
    >>> preserves.stringify(Float(3.45))
    '3.45f'
    >>> preserves.stringify(3.45)
    '3.45'
    >>> preserves.parse('3.45f')
    Float(3.45)
    >>> preserves.parse('3.45')
    3.45
    >>> preserves.encode(Float(3.45))
    b'\x82@\\\xcc\xcd'
    >>> preserves.encode(3.45)
    b'\x83@\x0b\x99\x99\x99\x99\x99\x9a'

Attributes:

Name | Type | Description
--- | --- | ---
`value` | `float` | the double-precision representation of intended single-precision value

Source code in `preserves/values.py`

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    def __init__(self, value):
        self.value = value

### `from_bytes(bs)` `staticmethod`

Converts a 4-byte-long byte string to a 32-bit single-precision floating point value wrapped in a Float instance. Takes care to preserve the quiet/signalling bit-pattern of NaN values, unlike its `struct.unpack('>f', ...)` equivalent.

    >>> Float.from_bytes(b'\x7f\x80\x00{')
    Float(nan)
    >>> Float.from_bytes(b'\x7f\x80\x00{').to_bytes()
    b'\x7f\x80\x00{'

    >>> struct.unpack('>f', b'\x7f\x80\x00{')[0]
    nan
    >>> Float(struct.unpack('>f', b'\x7f\x80\x00{')[0]).to_bytes()
    b'\x7f\xc0\x00{'
    >>> struct.pack('>f', struct.unpack('>f', b'\x7f\x80\x00{')[0])
    b'\x7f\xc0\x00{'

(Note well the difference between `7f80007b` and `7fc0007b`!)

Source code in `preserves/values.py`

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    @staticmethod
    def from_bytes(bs):
        """Converts a 4-byte-long byte string to a 32-bit single-precision floating point value
        wrapped in a [Float][preserves.values.Float] instance. Takes care to preserve the
        quiet/signalling bit-pattern of NaN values, unlike its `struct.unpack('>f', ...)`
        equivalent.

        ```python
        >>> Float.from_bytes(b'\\x7f\\x80\\x00{')
        Float(nan)
        >>> Float.from_bytes(b'\\x7f\\x80\\x00{').to_bytes()
        b'\\x7f\\x80\\x00{'

        >>> struct.unpack('>f', b'\\x7f\\x80\\x00{')[0]
        nan
        >>> Float(struct.unpack('>f', b'\\x7f\\x80\\x00{')[0]).to_bytes()
        b'\\x7f\\xc0\\x00{'
        >>> struct.pack('>f', struct.unpack('>f', b'\\x7f\\x80\\x00{')[0])
        b'\\x7f\\xc0\\x00{'

        ```

        (Note well the difference between `7f80007b` and `7fc0007b`!)

        """
        vf = struct.unpack('>I', bs)[0]
        if (vf & 0x7f800000) == 0x7f800000:
            # NaN or inf. Preserve quiet/signalling bit by manually expanding to double-precision.
            sign = vf >> 31
            payload = vf & 0x007fffff
            dbs = struct.pack('>Q', (sign << 63) | 0x7ff0000000000000 | (payload << 29))
            return Float(struct.unpack('>d', dbs)[0])
        else:
            return Float(struct.unpack('>f', bs)[0])

### `to_bytes()`

Converts this 32-bit single-precision floating point value to its binary32 format, taking care to preserve the quiet/signalling bit-pattern of NaN values, unlike its `struct.pack('>f', ...)` equivalent.

    >>> Float.from_bytes(b'\x7f\x80\x00{')
    Float(nan)
    >>> Float.from_bytes(b'\x7f\x80\x00{').to_bytes()
    b'\x7f\x80\x00{'

    >>> struct.unpack('>f', b'\x7f\x80\x00{')[0]
    nan
    >>> Float(struct.unpack('>f', b'\x7f\x80\x00{')[0]).to_bytes()
    b'\x7f\xc0\x00{'
    >>> struct.pack('>f', struct.unpack('>f', b'\x7f\x80\x00{')[0])
    b'\x7f\xc0\x00{'

(Note well the difference between `7f80007b` and `7fc0007b`!)

Source code in `preserves/values.py`

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    def to_bytes(self):
        """Converts this 32-bit single-precision floating point value to its binary32 format,
        taking care to preserve the quiet/signalling bit-pattern of NaN values, unlike its
        `struct.pack('>f', ...)` equivalent.

        ```python
        >>> Float.from_bytes(b'\\x7f\\x80\\x00{')
        Float(nan)
        >>> Float.from_bytes(b'\\x7f\\x80\\x00{').to_bytes()
        b'\\x7f\\x80\\x00{'

        >>> struct.unpack('>f', b'\\x7f\\x80\\x00{')[0]
        nan
        >>> Float(struct.unpack('>f', b'\\x7f\\x80\\x00{')[0]).to_bytes()
        b'\\x7f\\xc0\\x00{'
        >>> struct.pack('>f', struct.unpack('>f', b'\\x7f\\x80\\x00{')[0])
        b'\\x7f\\xc0\\x00{'

        ```

        (Note well the difference between `7f80007b` and `7fc0007b`!)

        """

        if math.isnan(self.value) or math.isinf(self.value):
            dbs = struct.pack('>d', self.value)
            vd = struct.unpack('>Q', dbs)[0]
            sign = vd >> 63
            payload = (vd >> 29) & 0x007fffff
            vf = (sign << 31) | 0x7f800000 | payload
            return struct.pack('>I', vf)
        else:
            return struct.pack('>f', self.value)

## `ImmutableDict(*args, **kwargs)`

Bases: `dict`

A subclass of Python's built-in `dict` that overrides methods that could mutate the dictionary, causing them to raise `TypeError('Immutable')` if called.

Implements the `__hash__` method, allowing ImmutableDict instances to be used whereever immutable data are permitted; in particular, as keys in other dictionaries.

    >>> d = ImmutableDict([('a', 1), ('b', 2)])
    >>> d
    {'a': 1, 'b': 2}
    >>> d['c'] = 3
    Traceback (most recent call last):
      ...
    TypeError: Immutable
    >>> del d['b']
    Traceback (most recent call last):
      ...
    TypeError: Immutable

Source code in `preserves/values.py`

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    def __init__(self, *args, **kwargs):
        if hasattr(self, '__hash'): raise TypeError('Immutable')
        super(ImmutableDict, self).__init__(*args, **kwargs)
        self.__hash = None

### `from_kvs(kvs)` `staticmethod`

Constructs an ImmutableDict from a sequence of alternating keys and values; compare to the ImmutableDict constructor, which takes a sequence of key-value pairs.

    >>> ImmutableDict.from_kvs(['a', 1, 'b', 2])
    {'a': 1, 'b': 2}
    >>> ImmutableDict.from_kvs(['a', 1, 'b', 2])['c'] = 3
    Traceback (most recent call last):
      ...
    TypeError: Immutable

Source code in `preserves/values.py`

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    @staticmethod
    def from_kvs(kvs):
        """Constructs an [ImmutableDict][preserves.values.ImmutableDict] from a sequence of
        alternating keys and values; compare to the
        [ImmutableDict][preserves.values.ImmutableDict] constructor, which takes a sequence of
        key-value pairs.

        ```python
        >>> ImmutableDict.from_kvs(['a', 1, 'b', 2])
        {'a': 1, 'b': 2}
        >>> ImmutableDict.from_kvs(['a', 1, 'b', 2])['c'] = 3
        Traceback (most recent call last):
          ...
        TypeError: Immutable

        ```

        """

        i = iter(kvs)
        result = ImmutableDict()
        result_proxy = super(ImmutableDict, result)
        try:
            while True:
                k = next(i)
                try:
                    v = next(i)
                except StopIteration:
                    raise DecodeError("Missing dictionary value")
                result_proxy.__setitem__(k, v)
        except StopIteration:
            pass
        return result

## `Record(key, fields)`

Bases: `object`

Representation of Preserves `Record`s, which are a pair of a label `Value` and a sequence of field `Value`s.

    >>> r = Record(Symbol('label'), ['field1', ['field2item1', 'field2item2']])
    >>> r
    #label('field1', ['field2item1', 'field2item2'])
    >>> r.key
    #label
    >>> r.fields
    ('field1', ['field2item1', 'field2item2'])
    >>> import preserves
    >>> preserves.stringify(r)
    '<label "field1" ["field2item1" "field2item2"]>'
    >>> r == preserves.parse('<label "field1" ["field2item1" "field2item2"]>')
    True

Parameters:

Name | Type | Description | Default
--- | --- | --- | ---
`key` | `Value` | the `Record`'s label | required
`fields` | `iterable[Value]` | the fields of the `Record` | required

Attributes:

Name | Type | Description
--- | --- | ---
`key` | `Value` | the `Record`'s label
`fields` | `tuple[Value]` | the fields of the `Record`

Source code in `preserves/values.py`

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    def __init__(self, key, fields):
        self.key = key
        self.fields = tuple(fields)
        self.__hash = None

### `makeBasicConstructor(label, fieldNames)` `staticmethod`

Constructs and returns a "constructor" for `Record`s having a certain `label` and number of fields.

Deprecated

Use preserves.schema definitions instead.

The "constructor" is a callable function that accepts `len(fields)` arguments and returns a Record with `label` as its label and the arguments to the constructor as field values.

In addition, the "constructor" has a `constructorInfo` attribute holding a RecordConstructorInfo object, an `isClassOf` attribute holding a unary function that returns `True` iff its argument is a Record with label `label` and arity `len(fieldNames)`, and an `ensureClassOf` attribute that raises an `Exception` if `isClassOf` returns false on its argument and returns the argument otherwise.

Finally, for each field name `f` in `fieldNames`, the "constructor" object has an attribute `_f` that is a unary function that retrieves the `f` field from the passed in argument.

    >>> c = Record.makeBasicConstructor(Symbol('date'), 'year month day')
    >>> c(1969, 7, 16)
    #date(1969, 7, 16)
    >>> c.constructorInfo
    #date/3
    >>> c.isClassOf(c(1969, 7, 16))
    True
    >>> c.isClassOf(Record(Symbol('date'), [1969, 7, 16]))
    True
    >>> c.isClassOf(Record(Symbol('date'), [1969]))
    False
    >>> c.ensureClassOf(c(1969, 7, 16))
    #date(1969, 7, 16)
    >>> c.ensureClassOf(Record(Symbol('date'), [1969]))
    Traceback (most recent call last):
      ...
    TypeError: Record: expected #date/3, got #date(1969)
    >>> c._year(c(1969, 7, 16))
    1969
    >>> c._month(c(1969, 7, 16))
    7
    >>> c._day(c(1969, 7, 16))
    16

Parameters:

Name | Type | Description | Default
--- | --- | --- | ---
`label` | `Value` | Label to use for constructed/matched `Record`s | required
`fieldNames` | `tuple[str] | list[str] | str` | Names of the `Record`'s fields | required

Source code in `preserves/values.py`

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    @staticmethod
    def makeBasicConstructor(label, fieldNames):
        """Constructs and returns a "constructor" for `Record`s having a certain `label` and
        number of fields.

        Deprecated:
           Use [preserves.schema][] definitions instead.

        The "constructor" is a callable function that accepts `len(fields)` arguments and
        returns a [Record][preserves.values.Record] with `label` as its label and the arguments
        to the constructor as field values.

        In addition, the "constructor" has a `constructorInfo` attribute holding a
        [RecordConstructorInfo][preserves.values.RecordConstructorInfo] object, an `isClassOf`
        attribute holding a unary function that returns `True` iff its argument is a
        [Record][preserves.values.Record] with label `label` and arity `len(fieldNames)`, and
        an `ensureClassOf` attribute that raises an `Exception` if `isClassOf` returns false on
        its argument and returns the argument otherwise.

        Finally, for each field name `f` in `fieldNames`, the "constructor" object has an
        attribute `_f` that is a unary function that retrieves the `f` field from the passed in
        argument.

        ```python
        >>> c = Record.makeBasicConstructor(Symbol('date'), 'year month day')
        >>> c(1969, 7, 16)
        #date(1969, 7, 16)
        >>> c.constructorInfo
        #date/3
        >>> c.isClassOf(c(1969, 7, 16))
        True
        >>> c.isClassOf(Record(Symbol('date'), [1969, 7, 16]))
        True
        >>> c.isClassOf(Record(Symbol('date'), [1969]))
        False
        >>> c.ensureClassOf(c(1969, 7, 16))
        #date(1969, 7, 16)
        >>> c.ensureClassOf(Record(Symbol('date'), [1969]))
        Traceback (most recent call last):
          ...
        TypeError: Record: expected #date/3, got #date(1969)
        >>> c._year(c(1969, 7, 16))
        1969
        >>> c._month(c(1969, 7, 16))
        7
        >>> c._day(c(1969, 7, 16))
        16

        ```

        Args:
            label (Value): Label to use for constructed/matched `Record`s
            fieldNames (tuple[str] | list[str] | str): Names of the `Record`'s fields

        """
        if type(fieldNames) == str:
            fieldNames = fieldNames.split()
        arity = len(fieldNames)
        def ctor(*fields):
            if len(fields) != arity:
                raise Exception("Record: cannot instantiate %r expecting %d fields with %d fields"%(
                    label,
                    arity,
                    len(fields)))
            return Record(label, fields)
        ctor.constructorInfo = RecordConstructorInfo(label, arity)
        ctor.isClassOf = lambda v: \
                         isinstance(v, Record) and v.key == label and len(v.fields) == arity
        def ensureClassOf(v):
            if not ctor.isClassOf(v):
                raise TypeError("Record: expected %r/%d, got %r" % (label, arity, v))
            return v
        ctor.ensureClassOf = ensureClassOf
        for fieldIndex in range(len(fieldNames)):
            fieldName = fieldNames[fieldIndex]
            # Stupid python scoping bites again
            def getter(fieldIndex):
                return lambda v: ensureClassOf(v)[fieldIndex]
            setattr(ctor, '_' + fieldName, getter(fieldIndex))
        return ctor

### `makeConstructor(labelSymbolText, fieldNames)` `staticmethod`

Equivalent to `Record.makeBasicConstructor(Symbol(labelSymbolText), fieldNames)`.

Deprecated

Use preserves.schema definitions instead.

Source code in `preserves/values.py`

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    @staticmethod
    def makeConstructor(labelSymbolText, fieldNames):
        """
        Equivalent to `Record.makeBasicConstructor(Symbol(labelSymbolText), fieldNames)`.

        Deprecated:
           Use [preserves.schema][] definitions instead.
        """
        return Record.makeBasicConstructor(Symbol(labelSymbolText), fieldNames)

## `RecordConstructorInfo(key, arity)`

Bases: `object`

Describes the shape of a `Record` constructor, namely its label and its arity (field count).

    >>> RecordConstructorInfo(Symbol('label'), 3)
    #label/3

Attributes:

Name | Type | Description
--- | --- | ---
`key` | `Value` | the label of matching `Record`s
`arity` | `int` | the number of fields in matching `Record`s

Source code in `preserves/values.py`

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    def __init__(self, key, arity):
        self.key = key
        self.arity = arity

## `Symbol(name)`

Bases: `object`

Representation of Preserves `Symbol`s.

    >>> Symbol('xyz')
    #xyz
    >>> Symbol('xyz').name
    'xyz'
    >>> import preserves
    >>> preserves.stringify(Symbol('xyz'))
    'xyz'
    >>> preserves.stringify(Symbol('hello world'))
    '|hello world|'
    >>> preserves.parse('xyz')
    #xyz
    >>> preserves.parse('|hello world|')
    #hello world

Attributes:

Name | Type | Description
--- | --- | ---
`name` | `str | Symbol` | The symbol's text label. If an existing Symbol is passed in, the existing Symbol's `name` is used as the `name` for the new Symbol.

Source code in `preserves/values.py`

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    def __init__(self, name):
        self.name = name.name if isinstance(name, Symbol) else name

## `annotate(v, *anns)`

Wraps `v` in an Annotated object, if it isn't already wrapped, and appends each of the `anns` to the Annotated's `annotations` sequence. NOTE: Does not recursively ensure that any parts of the argument `v` are themselves wrapped in Annotated objects!

    >>> import preserves
    >>> print(preserves.stringify(annotate(123, "A comment", "Another comment")))
    @"A comment" @"Another comment" 123

Source code in `preserves/values.py`

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    def annotate(v, *anns):
        """Wraps `v` in an [Annotated][preserves.values.Annotated] object, if it isn't already
        wrapped, and appends each of the `anns` to the [Annotated][preserves.values.Annotated]'s
        `annotations` sequence. NOTE: Does not recursively ensure that any parts of the argument
        `v` are themselves wrapped in [Annotated][preserves.values.Annotated] objects!

        ```python
        >>> import preserves
        >>> print(preserves.stringify(annotate(123, "A comment", "Another comment")))
        @"A comment" @"Another comment" 123

        ```
        """
        if not is_annotated(v):
            v = Annotated(v)
        for a in anns:
            v.annotations.append(a)
        return v

## `cmp_floats(a, b)`

Implements the `totalOrder` predicate defined in section 5.10 of IEEE Std 754-2008.

Source code in `preserves/values.py`

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    def cmp_floats(a, b):
        """Implements the `totalOrder` predicate defined in section 5.10 of [IEEE Std
        754-2008](https://dx.doi.org/10.1109/IEEESTD.2008.4610935).

        """
        a = float_to_int(a)
        b = float_to_int(b)
        if a & 0x8000000000000000: a = a ^ 0x7fffffffffffffff
        if b & 0x8000000000000000: b = b ^ 0x7fffffffffffffff
        return a - b

## `dict_kvs(d)`

Generator function yielding a sequence of alternating keys and values from `d`. In some sense the inverse of ImmutableDict.from_kvs.

    >>> list(dict_kvs({'a': 1, 'b': 2}))
    ['a', 1, 'b', 2]

Source code in `preserves/values.py`

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    def dict_kvs(d):
        """Generator function yielding a sequence of alternating keys and values from `d`. In some
        sense the inverse of [ImmutableDict.from_kvs][preserves.values.ImmutableDict.from_kvs].

        ```python
        >>> list(dict_kvs({'a': 1, 'b': 2}))
        ['a', 1, 'b', 2]

        ```
        """
        for k in d:
            yield k
            yield d[k]

## `is_annotated(v)`

`True` iff `v` is an instance of Annotated.

Source code in `preserves/values.py`

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    def is_annotated(v):
        """`True` iff `v` is an instance of [Annotated][preserves.values.Annotated]."""
        return isinstance(v, Annotated)

## `preserve(v)`

Converts `v` to a representation of a Preserves `Value` by (repeatedly) setting

    v = v.__preserve__()

while `v` has a `__preserve__` method. Parsed Schema values are able to render themselves to their serialized representations this way.

Source code in `preserves/values.py`

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    def preserve(v):
        """Converts `v` to a representation of a Preserves `Value` by (repeatedly) setting

        ```python
        v = v.__preserve__()
        ```

        while `v` has a `__preserve__` method. Parsed [Schema][preserves.schema]
        values are able to render themselves to their serialized representations this way.

        """
        while hasattr(v, '__preserve__'):
            v = v.__preserve__()
        return v

## `strip_annotations(v, depth=inf)`

Exposes `depth` layers of raw structure of potentially-Annotated `Value`s. If `depth==0` or `v` is not Annotated, just returns `v`. Otherwise, descends recursively into the structure of `v.item`.

    >>> import preserves
    >>> a = preserves.parse('@"A comment" [@a 1 @b 2 @c 3]', include_annotations=True)
    >>> is_annotated(a)
    True
    >>> print(preserves.stringify(a))
    @"A comment" [@a 1 @b 2 @c 3]
    >>> print(preserves.stringify(strip_annotations(a)))
    [1 2 3]
    >>> print(preserves.stringify(strip_annotations(a, depth=1)))
    [@a 1 @b 2 @c 3]

Source code in `preserves/values.py`

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    def strip_annotations(v, depth=inf):
        """Exposes `depth` layers of raw structure of
        potentially-[Annotated][preserves.values.Annotated] `Value`s. If `depth==0` or `v` is not
        [Annotated][preserves.values.Annotated], just returns `v`. Otherwise, descends recursively
        into the structure of `v.item`.

        ```python
        >>> import preserves
        >>> a = preserves.parse('@"A comment" [@a 1 @b 2 @c 3]', include_annotations=True)
        >>> is_annotated(a)
        True
        >>> print(preserves.stringify(a))
        @"A comment" [@a 1 @b 2 @c 3]
        >>> print(preserves.stringify(strip_annotations(a)))
        [1 2 3]
        >>> print(preserves.stringify(strip_annotations(a, depth=1)))
        [@a 1 @b 2 @c 3]

        ```
        """

        if depth == 0: return v
        if not is_annotated(v): return v

        next_depth = depth - 1
        def walk(v):
            return strip_annotations(v, next_depth)

        v = v.item
        if isinstance(v, Record):
            return Record(strip_annotations(v.key, depth), tuple(walk(f) for f in v.fields))
        elif isinstance(v, list):
            return tuple(walk(f) for f in v)
        elif isinstance(v, tuple):
            return tuple(walk(f) for f in v)
        elif isinstance(v, set):
            return frozenset(walk(f) for f in v)
        elif isinstance(v, frozenset):
            return frozenset(walk(f) for f in v)
        elif isinstance(v, dict):
            return ImmutableDict.from_kvs(walk(f) for f in dict_kvs(v))
        elif is_annotated(v):
            raise ValueError('Improper annotation structure')
        else:
            return v

Last update: March 16, 2023
Created: March 16, 2023