[Python-Dev] PEP 550 v4 (original) (raw)

Greg Ewing greg.ewing at canterbury.ac.nz
Thu Sep 7 03:54:15 EDT 2017

Yury Selivanov wrote:

def foo(): var = ContextVar() var.set(1)

for in range(10**6): foo() If 'var' is strongly referenced, we would have a bunch of them.

Erk. This is not how I envisaged context vars would be used. What I thought you would do is this:

my_context_var = ContextVar()

def foo():
   my_context_var.set(1)

This problem would also not arise if context vars simply had names instead of being magic key objects:

def foo():
   contextvars.set("mymodule.myvar", 1)

That's another thing I think would be an improvement, but it's orthogonal to what we're talking about here and would be best discussed separately.

-- Greg

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