Is this a safe thing to do?

[Terry Reedy]

"Duncan Booth" <duncan at NOSPAMrcp.co.uk> wrote in message
news:Xns940F8C176F22Bduncanrcpcouk at 127.0.0.1...
> The answer is to iterate over a COPY of the list if you want to
modify it
> during the iteration:

or, when deleting items, carefully iterate backwards

x=[{'f':9},{'f':1},{1:3,'f':9},{'f':9},{'f':3}]
for i in range(len(x)-1,-1,-1):
    if x[i]['f'] == 9:
        del x[i]

>>> x
[{'f': 1}, {'f': 3}]

Terry J. Reedy