def max_(
comparer: Optional[Comparer[_T]] = None,
) -> Callable[[Observable[_T]], Observable[_T]]:
"""Returns the maximum value in an observable sequence according to
the specified comparer.
Examples:
>>> op = max()
>>> op = max(lambda x, y: x.value - y.value)
Args:
comparer: [Optional] Comparer used to compare elements.
Returns:
An operator function that takes an observable source and returns
an observable sequence containing a single element with the
maximum element in the source sequence.
"""
return compose(
ops.max_by(identity, comparer),
ops.map(first_only),
)
def create():
def mapper(x):
return x["key"]
return xs.pipe(ops.max_by(mapper))
def create():
return xs.pipe(ops.max_by(lambda x: x["key"], reverse_comparer))
def create():
return xs.pipe(ops.max_by(lambda x: x["key"]))