Hi Oscar,
I don't think PyPy is in breach of the language spec here. Python made
a decision a long time ago to shun RAII-style implicit cleanup in
favour if with-style explicit cleanup.
The solution to this problem is to move resource management outside of
the generator functions. This is true for ordinary generators without
an event-loop etc. The example in the PEP is
async def square_series(con, to):
async with con.transaction():
cursor = con.cursor(
'SELECT generate_series(0, $1) AS i', to)
async for row in cursor:
yield row['i'] ** 2
async for i in square_series(con, 1000):
if i == 100:
break
The normal generator equivalent of this is:
def square_series(con, to):
with con.transaction():
cursor = con.cursor(
'SELECT generate_series(0, $1) AS i', to)
for row in cursor:
yield row['i'] ** 2
This code is already broken: move the with statement outside to the
caller of the generator function.
Exactly.
I used 'async with' in the PEP to demonstrate that the cleanup
mechanisms are powerful enough to handle bad code patterns.
Thank you,
Yury
_______________________________________________
Python-Dev mailing list
Python-Dev@python.org
https://mail.python.org/mailman/listinfo/python-dev
Unsubscribe:
https://mail.python.org/mailman/options/python-dev/archive%40mail-archive.com
