Thank you everybody. This was very helpful Monika ---------- Original Message ---------- From: Steven D'Aprano <st...@pearwood.info> To: tutor@python.org Subject: Re: [Tutor] generator object Date: Wed, 31 Aug 2016 21:24:57 +1000
On Wed, Aug 31, 2016 at 04:12:24AM +0000, monik...@netzero.net wrote: > > So generator function returns generator object according to Aaron > Maxwell. But does this mean that each time yields "returns" it is a > generator object? So if there are 5 yield "returns" there are 5 > generator objects? Or is there always only one generator object > returned by the generator functions? > Can somebody please explain? The terminology can be confusing, because there are multiple very similar terms which are related. But fortunately, we can ask Python itself for help! Let's start by using the inspect module to take a look at an ordinary function: py> import inspect py> def func(): ... return 19 ... py> inspect.isfunction(func) True py> inspect.isgenerator(func) False py> inspect.isgeneratorfunction(func) False So that's pretty straight-forward: a regular function is just a function. What happens if we make something which people often call "a generator"? Let's make a function and use yield instead of return: py> def gen(): ... yield 19 ... py> inspect.isfunction(gen) True py> inspect.isgenerator(gen) False py> inspect.isgeneratorfunction(gen) True So there you have it: a function with "yield" inside is still a function, but it is also a "generator function". Even though people often call it "a generator", it isn't technically a generator. It's a generator function. If we call the generator function, what do we get? py> it = gen() py> inspect.isfunction(it) False py> inspect.isgenerator(it) True py> inspect.isgeneratorfunction(it) False So there we have it, all official: calling a generator FUNCTION returns a generator. But in practice, people will use the term "generator" for both generator functions like "gen", and the actual generators like "it". Normally the distinction isn't important, or it is obvious. When it isn't obvious, you can avoid ambiguity by referring to "gen" as the generator function, and "it" as the generator object. -- Steve _______________________________________________ Tutor maillist - Tutor@python.org To unsubscribe or change subscription options: https://mail.python.org/mailman/listinfo/tutor ____________________________________________________________ moneynews.com (Sponsored by Content.Ad) 5 Stocks to Buy Now | Massive Market Correction http://thirdpartyoffers.netzero.net/TGL3241/57c70d06c606fd062da7st02duc _______________________________________________ Tutor maillist - Tutor@python.org To unsubscribe or change subscription options: https://mail.python.org/mailman/listinfo/tutor
