[Python-Dev] (name := expression) doesn't fit the narrative of PEP 20

[Greg Ewing]

Tim Peters wrote:
> As a statement in a program (as opposed to typed at a shell),
> "a := 3" has the unnecessary (in that context) property of returning
> (and discarding 3), so it's better style to use "a = 3" in that
> context.

That seems like a post-hoc justification. If := were the one
and only assignment symbol, the compiler could easily optimise
away the extra DUP_TOP or whatever is involved.

-- 
Greg