On Tue, Jan 20, 2026 at 09:59:11AM +0100, Gabriele Monaco wrote: > On Mon, 2026-01-19 at 17:45 -0300, Wander Lairson Costa wrote: > > Initialize loop variable `i` before the for loop in abbreviate_atoms > > function to fix pyright static type checker error. The previous code > > left `i` potentially unbound in edge cases where the range could be > > empty, though this would not occur in practice since the loop always > > executes at least once with the given range parameters. > > > > The initialization to zero ensures that `i` has a defined value before > > entering the loop scope, satisfying static analysis requirements > > while preserving the existing logic. The for loop immediately assigns > > i to the first value from the range, so the initialization value is > > never actually used in normal execution paths. > > > > This change resolves the pyright reportPossiblyUnbound error without > > altering the function's behavior or performance characteristics. > > So are we just pleasing the tool or is there a real implication of this? > > Apparently code like > > for i in range(len([]), -1, -1): > pass > print(i) > > works just fine since range() returns at least 0 (as you mentioned in the > commit > message) and i is not used before assignation in the loop, so I don't really > see > a problem. > > Apparently pyright devs don't want ([1]) to implement a logic to sort out the > /possibly/ unbound error here. > > From what I understand, this code is already not pythonic, so rather than > silence the warning to please this tool I'd just refactor the code not to use > i > after the loop (or leave it as it is, since it works fine). > > What do you think?
You're right, I could have done: for atom in reversed(atoms): ... I will modify it in v2. > > Thanks, > Gabriele > > [1] - https://github.com/microsoft/pyright/issues/844 > > > > > Signed-off-by: Wander Lairson Costa <[email protected]> > > --- > > tools/verification/rvgen/rvgen/ltl2k.py | 1 + > > 1 file changed, 1 insertion(+) > > > > diff --git a/tools/verification/rvgen/rvgen/ltl2k.py > > b/tools/verification/rvgen/rvgen/ltl2k.py > > index fa9ea6d597095..94dc64af1716d 100644 > > --- a/tools/verification/rvgen/rvgen/ltl2k.py > > +++ b/tools/verification/rvgen/rvgen/ltl2k.py > > @@ -45,6 +45,7 @@ def abbreviate_atoms(atoms: list[str]) -> list[str]: > > > > abbrs = [] > > for atom in atoms: > > + i = 0 > > for i in range(len(atom), -1, -1): > > if sum(a.startswith(atom[:i]) for a in atoms) > 1: > > break >
