Function _unique_symbols

lib/sqlalchemy/util/langhelpers.py:233–246

(used: Sequence[str], *bases: str)

def _unique_symbols(used: Sequence[str], *bases: str) -> Iterator[str]:
    used_set = set(used)
    for base in bases:
        pool = itertools.chain(
            (base,),
            map(lambda i: base + str(i), range(1000)),
        )
        for sym in pool:
            if sym not in used_set:
                used_set.add(sym)
                yield sym
                break
        else:
            raise NameError("exhausted namespace for symbol base %s" % base)


def map_bits(fn: Callable[[int], Any], n: int) -> Iterator[Any]: