param.reactive.reactive_ops.in_

reactive_ops.in_(other) → rx

Check if the current object is contained “in” the given operand.

This method performs a containment check, equivalent to the in keyword in Python, but within a reactive expression. The result is returned as a new reactive expression.

Parameters:

other (any) – The collection or operand to check for containment.

Returns:

A new reactive expression representing the result of the containment check.

Return type:

rx

Examples

Check if a reactive value is in a list:

>>> import param
>>> rx_value = param.rx(2)
>>> rx_in = rx_value.rx.in_([1, 2, 3])
>>> rx_in.rx.value
True

Check containment with a string:

>>> rx_char = param.rx('a')
>>> rx_in = rx_char.rx.in_('alphabet')
>>> rx_in.rx.value
True

Update the reactive value and observe changes:

>>> rx_char.rx.value = 'c'
>>> rx_in.rx.value
False