Usage

class atomic.Atomic(value=None)

An atomic class that guarantees atomic updates to its contained value.

compare_and_set(expect_value, new_value)

Atomically sets the value to the given value if the current value is equal to the expected value.

Parameters:

• expect_value – the expected value
• new_value – the new value

get_and_set(new_value)

Atomically sets to the given value and returns the old value

Parameters:new_value – the new value

try_update(update_func)

Update value based on the given function.

If the value changes before the update can happen, it will raise a ConcurrentUpdateException.

Parameters:update_func (func) – a function that given the current value return the new value Raises :ConcurrentUpdateException

update(update_func)

Update value based on the given function.

It may run the block repeatedly if there are other concurrent updates in progress.

Parameters:update_func (func) – a function that given the current value return the new value

value

Get and set current value