On Thu, Apr 26, 2018 at 3:34 PM, Steven D'Aprano <steve@pearwood.info> wrote:
On Thu, Apr 26, 2018 at 05:22:58PM +1200, Greg Ewing wrote:
Łukasz Langa wrote:
What was its own assignment before now is part of the logic test. This saves on vertical whitespace but makes parsing and understanding logic tests harder.
Another way to say this is that expressions are no longer restricted to being trees, but can be general DAGs, which require more mental effort to understand.
Is that right? I presume you mean that there can be cycles in expressions involving binding-expressions. If not, what do you mean?
Can you give an example of a Python expression, involving PEP 572 binding-expressions, that is not a tree but a more general DAG or that contains cycles?
A DAG is a directed *acyclic* graph, so it still can't contain cycles. But I have no idea what kind of expression isn't a tree as a consequence of having an assignment in it. ChrisA