Steven D'Aprano wrote: <snip>
The only case it doesn't cover is where the second filter depends on the value of x, and even that can be covered with a *tiny* bit more work:
gen = ((x, 3*x**2-5*x+4) for x in seq if x % 3 != 2) result = [y[1] for y in gen if -y[0] < y[1] < y[0]]
It requires no new syntax, no changes to the behaviour of list comps, no new meaning on "as", it's understandable and readable.
Compare your suggestion:
[3*x**2-5*x+4 as y for x in seq if (x % 3 != 2) and (-x < y < x)]
For me, this one is much clearer, understandable, and readable than y[0] and y[1]; and you still have the option to split them if you think y[0] and y[1] is better.
Disadvantages:
- It requires new syntax. - It requires new behaviour to list comps and generator expressions. - It creates yet another meaning to the keyword "as".
"as" is already used for renaming keyword in "with" and "import" statement, so I don't think it actually creates any more meaning that we don't already have.