On 10.05.2018 15:57, Guido van Rossum wrote:
On Thu, May 10, 2018 at 5:04 AM, M.-A. Lemburg <mal@egenix.com> wrote:
To a (former Pascal) programmer, a := 1 doesn't read like an operator. It's an assignment expression. If embedded expressions is where Python is heading, it should be made very clear where the embedded expression starts and where it ends on a line.
The rules we've arrived at are about as straightforward as it gets: the RHS of `:=` ends at the nearest comma or close parenthesis/bracket/brace.
That may be easy for a computer to parse, but it's not for a programmer. It would be better to contain such expressions inside a safe container which is clearly visible to a human eye. ohoh = a := (1, 2, 3), 4, a * 2 vs. aha = ((a := (1, 2, 3)), 4, a * 2) You'd simplify the above logic to: the RHS of ":=" ends at the nearest closing parenthesis.
OT about the name: despite Tim's relentless pushing of "binding expressions" in the end I think they should be called "assignment expressions" just like in C.
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