iterator - Python: is iter(x) equivalent to for el in x: yield el? -

iterator - Python: is iter(x) equivalent to for el in x: yield el? -

suppose there collection:

list = [1,2,3]

is builtin method

it1 = iter(list)

equivalent to

def niter(x): el in x: yield el it2 = niter(list)

edit: to farther clarify, know iter() can except more arguments, in principal want know if same yield doing in niter

no. iter(lst) returns list_iterator object, sec illustration generic generator. both same, in different ways. xxx_iterator objects aware of construction iterating on, , utilize specific properties implement next method. generic generators don't know arguments (if any) , rely on them implement iterator protocol. iter(lst) returns real iterator, 1 fetches items list, , niter wrapper simply delegates job argument (which happens list_iterator 1 time again).

in other words iter(obj) says "dear obj, need knows how iterate you" , for z in obj "i don't care how iterate you, gimme values".

python iterator