python - isinstance(x, list) when iterating a list containing strings and lists -

python - isinstance(x, list) when iterating a list containing strings and lists -

at iterating nested list inside-out, told "type-checking isn't pythonic". generally, true: want @ interface (duck-typing) rather specific type.

the question asks nested lists of form ['a', ['c', ['e'], 'd'], 'b'], , consider strings atomic (non-iterable). so, can't utilize blanket collections.iterable, on other hand isinstance(x, list) seem bit hacky.

my reply was

def traverse(l): x in l: if isinstance(x, list): traverse(x) callback(l)

what's improve approach? or isinstance ok here?

i think reply ok here -- although might alter

if not isinstance(x,basestring): ...

to create little more accepting depending on expected input. ultimately, problems need isinstance why still exists in language.

that beingness said, thing problem un-pythonic data-structure. in python, if problem seems hard, means you're storing info in wrong way ... (of course, realize had no command on original poster of other question's info construction ;-).

basically, guess view isinstance hack need create lemonade when colleagues/some library author somewhere gives lemons -- otherwise avoid possible.

python collections iterable