Add periodic flash for computing variables

[davidbrochart]

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[stefaneidelloth]

Thanks a lot for the fast implementation!

I tried with following cells:

b=a+1
a

import time
def calc_a():
    time.sleep(3)
    return 30

a = calc_a()
a

I would expect the first cell to be marked while method calc_a is executed. However, it seems that the first cell is flashing after the method call is finished.

I also tried to wrap the function with ipyx.F. However, then the first cell seems to flash for ever:

import time
from ipyx import X, F
def calc_a():
    time.sleep(3)
    return 10
f = F(calc_a)
a = f()
a

=> What is the right way to define reactive cells and what is the expected behavior for the flashing feature?

[davidbrochart]

Here calc_a doesn't appear in the data flow, it's just used as an input to a. You should see the flashing behavior with something like that:

# cell 1
import time
from ipyx import X, F

def _f(x):
    time.sleep(3)
    return x + 30

f = F(_f)

# cell 2
a = X()
a

# cell 3
b = f(a)
b

# cell 4
a.v = 1  # should make b flash during 3 seconds

There is a bug when you assign the same value (like when re-executing cell 4), the flashing doesn't stop. I will push a fix.