Peekable

@dataclass(slots=True)
class Peekable[T](Pipeable, Checkable):
    """Represents the result of peeking into an `Iter`.

    Inerhit from `Checkable` to provide truthiness based on whether any elements were peeked.

    Attributes:
        peek (Seq[T]): A `Seq` of the peeked elements.
        values (Iter[T]): An `Iter` of values, still including the peeked elements.

    See Also:
        `Iter.peekable()`
        `Iter.cloned()`

    Example:
    ```python
    >>> import pyochain as pc
    >>> it = pc.Iter([1, 2, 3, 4, 5])
    >>> peekable = it.peekable(3)
    >>> peekable.peek
    Seq(1, 2, 3)
    >>> peekable.values.collect()
    Seq(1, 2, 3, 4, 5)

    ```
    """

    peek: Seq[T]
    """A `Seq` of the peeked elements."""
    values: Iter[T]
    """An `Iter` of values, still including the peeked elements."""

    def __bool__(self) -> bool:
        return bool(self.peek)