between

validators.between.between(value, /, *, min_val=None, max_val=None)

Validate that a number is between minimum and/or maximum value.

This will work with any comparable type, such as floats, decimals and dates not just integers. This validator is originally based on WTForms-NumberRange-Validator.

Examples:

>>> from datetime import datetime
>>> between(5, min_val=2)
# Output: True
>>> between(13.2, min_val=13, max_val=14)
# Output: True
>>> between(500, max_val=400)
# Output: ValidationError(func=between, args=...)
>>> between(
...     datetime(2000, 11, 11),
...     min_val=datetime(1999, 11, 11)
... )
# Output: True

Parameters:

Name	Type	Description	Default
value	PossibleValueTypes	Value which is to be compared.	required
min_val	Union[PossibleValueTypes, AbsMin, None]	The minimum required value of the number. If not provided, minimum value will not be checked.	None
max_val	Union[PossibleValueTypes, AbsMax, None]	The maximum value of the number. If not provided, maximum value will not be checked.	None

Returns:

Type	Description
Literal[True]	If value is in between the given conditions.
ValidationError	If value is not in between the given conditions.

Raises:

Type	Description
ValueError	If min_val is greater than max_val.
TypeError	If there's a type mismatch during comparison.

Note

• PossibleValueTypes = TypeVar("PossibleValueTypes", int, float, str, datetime)
• If neither min_val nor max_val is provided, result will always be True.

Source code in src/validators/between.py

@validator
def between(
    value: PossibleValueTypes,
    /,
    *,
    min_val: Union[PossibleValueTypes, AbsMin, None] = None,
    max_val: Union[PossibleValueTypes, AbsMax, None] = None,
):
    """Validate that a number is between minimum and/or maximum value.

    This will work with any comparable type, such as floats, decimals and dates
    not just integers. This validator is originally based on [WTForms-NumberRange-Validator][1].

    [1]: https://github.com/wtforms/wtforms/blob/master/src/wtforms/validators.py#L166-L220

    Examples:
        >>> from datetime import datetime
        >>> between(5, min_val=2)
        # Output: True
        >>> between(13.2, min_val=13, max_val=14)
        # Output: True
        >>> between(500, max_val=400)
        # Output: ValidationError(func=between, args=...)
        >>> between(
        ...     datetime(2000, 11, 11),
        ...     min_val=datetime(1999, 11, 11)
        ... )
        # Output: True

    Args:
        value:
            Value which is to be compared.
        min_val:
            The minimum required value of the number.
            If not provided, minimum value will not be checked.
        max_val:
            The maximum value of the number.
            If not provided, maximum value will not be checked.

    Returns:
        (Literal[True]): If `value` is in between the given conditions.
        (ValidationError): If `value` is not in between the given conditions.

    Raises:
        (ValueError): If `min_val` is greater than `max_val`.
        (TypeError): If there's a type mismatch during comparison.

    Note:
        - `PossibleValueTypes` = `TypeVar("PossibleValueTypes", int, float, str, datetime)`
        - If neither `min_val` nor `max_val` is provided, result will always be `True`.
    """
    if value is None:
        return False

    if max_val is None:
        max_val = AbsMax()
    if min_val is None:
        min_val = AbsMin()

    try:
        if min_val > max_val:
            raise ValueError("`min_val` cannot be greater than `max_val`")
    except TypeError as err:
        raise TypeError("Comparison type mismatch") from err

    return min_val <= value <= max_val