Re: Connection refused when tryign to run bottle/flask web framweworks
On 08/20/2018 06:07 AM, Νίκος wrote: > Iam trying to access the bottle web framework running on my VPS as > > http://superhost.gr:8080/hello > > i get connection refused > The weird thing is that in my vps command line my hello app is in state of > listening > > [root@superhost public_html]# python3 app.py > Bottle v0.12.13 server starting up (using WSGIRefServer())... > Listening on http://localhost:8080/ > Hit Ctrl-C to quit. > > So, i wonder why the socket with port 8080 aint being displayed. Why do you wonder? You're using the wrong url. The message that's displayed when you start your mini app says it's listening on localhost, which is 127.0.0.1. Yet you are trying to access the url http://superhost.gr:8080/hello, which is a completely different IP address. For security reasons while you're debugging and developing, most web frameworks bind to localhost, not your public address. So you need to access it via localhost: http://localhost:8080/hello If you notice, this is the exact url that your program told you it was listening on. It is possible to configure flask to listen on "*.*.*.*" which means listen on all interfaces, localhost as well as the outside address. But this is not recommended. Instead you would publish it to the outside world through another web server like Apache. -- https://mail.python.org/mailman/listinfo/python-list
Re: Connection refused when tryign to run bottle/flask web framweworks
Τη Δευτέρα, 20 Αυγούστου 2018 - 7:18:16 μ.μ. UTC+3, ο χρήστης Chris Warrick
έγραψε:
> On Mon, 20 Aug 2018 at 18:15, Νίκος wrote:
> >
> > Τη Δευτέρα, 20 Αυγούστου 2018 - 9:49:00 π.μ. UTC+3, ο χρήστης Miki Tebeka
> > έγραψε:
> > > If you're trying to access the machine from another machine, you need to
> > > change the host to '0.0.0.0'. 'localhost' is the internal interface.
> > >
> > > On Sunday, August 19, 2018 at 10:36:25 PM UTC+3, Νίκος wrote:
> > > > Hello,
> > > >
> > > > i just installed bottle and flask web frameworks in my CentOS
> > > > environment but i canno get it working even with the simpleste xample.
> > > > The coonection is refused always.
> > > >
> > > > from bottle import route, run, template
> > > >
> > > > @route('/hello/')
> > > > def index(name):
> > > > return template('Hello {{name}}!', name=name)
> > > >
> > > > run(host='localhost', port=8080)
> > > >
> > > >
> > > > Any ideas as to why i cannot access it?
> > > > I dont have sme firewall blocking the ports 8080 or 5000.
> > > >
> > > > Thank you.
> >
> > 0.0.0.0 is used when you want your app to lsiten to all available
> > interfaces. Even with that still i cannot access the hello app.
>
> You should avoid exposing the built-in web server to the Internet.
> Either way, are you sure you don’t have any firewall set up on the
> server?
Yes, as far as i know i dont have any firewal installed, i use
webmin/virtulamin and i have uninstalled firewalld.
How can i check if some other firewall like iptables or somethign else is
blocking the connection?
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Re: Connection refused when tryign to run bottle/flask web framweworks
Τη Τρίτη, 21 Αυγούστου 2018 - 4:39:50 μ.μ. UTC+3, ο χρήστης Michael Torrie έγραψε: > On 08/20/2018 06:07 AM, Νίκος wrote: > > Iam trying to access the bottle web framework running on my VPS as > > > > http://superhost.gr:8080/hello > > > > i get connection refused > > > The weird thing is that in my vps command line my hello app is in state of > > listening > > > > [root@superhost public_html]# python3 app.py > > Bottle v0.12.13 server starting up (using WSGIRefServer())... > > Listening on http://localhost:8080/ > > Hit Ctrl-C to quit. > > > > So, i wonder why the socket with port 8080 aint being displayed. > > Why do you wonder? You're using the wrong url. The message that's > displayed when you start your mini app says it's listening on localhost, > which is 127.0.0.1. Yet you are trying to access the url > http://superhost.gr:8080/hello, which is a completely different IP > address. > > For security reasons while you're debugging and developing, most web > frameworks bind to localhost, not your public address. So you need to > access it via localhost: > > http://localhost:8080/hello > > If you notice, this is the exact url that your program told you it was > listening on. > > It is possible to configure flask to listen on "*.*.*.*" which means > listen on all interfaces, localhost as well as the outside address. But > this is not recommended. Instead you would publish it to the outside > world through another web server like Apache. But my mini app runds on my remote VPS and iam trying to access it from my windows 10 machine. Also '0.0.0.0' which listen to all network interfaces on the VPS still isn't allowing the mini app to be access from the outside world. Should i try superhost.gr/ip address in order to access it? -- https://mail.python.org/mailman/listinfo/python-list
Re: Pylint false positives
On Tue, 21 Aug 2018 00:36:56 +, Dan Sommers wrote: [...] (Not that I do this using "inner classes", but I do often want to use a class as a container for functions, without caring about "self" or wrapping everything in staticmethod.) >>> >>> Isn't that what modules are for? (I suspect that I'm missing >>> something, because I also suspect that you knew/know that.) >> >> What's the syntax for creating an inner module...? > > Why does it have to be an inner anything? An ordinary, top-level, > "outer" module is a perfectly good "container for functions, without > caring about "self."" And what if you want to subdivide those functions (or other objects) into categories that are finer than the module, without introducing a package structure? We can design the structure of our program into *outward* hierarchies, by adding packages with subpackages and sub-subpackages: import spam.eggs.cheese.tomato.aardvark So using the file system and packages, we can logically nest modules inside modules inside modules 'til the cows come home. But that's a fairly heavyweight solution, in the sense that it requires separate directory for each level of the hierarchy. Sometimes a package is too much. I want a single module file, but still want to pull out a collection of related functions and other objects and put them in their own namespace, but without creating a new module. The Zen says: Namespaces are one honking great idea -- let's do more of those! but Python's namespaces are relatively impoverished. We have packages, modules, classes and instances, and that's it. Classes and instances come with inheritance, self etc which is great if you want a class, but if you just want a simple module-like namespace without the extra file, classes are a pretty poor alternative. But they're all we've got. -- Steven D'Aprano "Ever since I learned about confirmation bias, I've been seeing it everywhere." -- Jon Ronson -- https://mail.python.org/mailman/listinfo/python-list
ignoring some default fields from SimpleJsonFormatter
I am using for my logger
handler.setFormatter(SimpleJsonFormatter(json.dumps))
It had some default fields - timestamp, function, line_number, module, level
and flexibility to provide extra fields in json log with use of
logger.info("my test message", extra={"anotherfield1": "test"})
I am using decorator functions so some of the default fields provided ex-
function, line_number, module are not useful as it gives information on
decorator module, line_number.
I like to remove some fields from being logged while retaining others, keeping
also the use of "extra"
This is what I tried -
logging.Formatter('{"timestamp": "%(asctime)s.%(msecs)06d",
"level":"%(levelname)s"}',
'%Y-%m-%dT%H:%M:%S')
The problem is that it doesn't print the fields given in 'extra'
How do I accomplish this?
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Project Structure for Backend ETL Project
Is this a good example to follow for a project that does mostly python to interact with external data sources including files, transformation, and import into Postgres? https://github.com/bast/somepackage I have a SWE background but not with python, and I want to make sure my team is following good practices. I am aware of pep8 but does that have project structure examples also? -- https://mail.python.org/mailman/listinfo/python-list
Is pypi the best place to find external python packages?
are there other places also? On pypi I did not see anywhere the status of defects or downloads, if it's actively supported. -- https://mail.python.org/mailman/listinfo/python-list
Re: Is pypi the best place to find external python packages?
On Tuesday, August 21, 2018 at 9:48:50 AM UTC-6, Jeff M wrote: > are there other places also? On pypi I did not see anywhere the status of > defects or downloads, if it's actively supported. nevermind, i see the info i was looking for on the left side. -- https://mail.python.org/mailman/listinfo/python-list
Saving application configuration to the ini file respecting order of sections/options and providing mechanism for (nested) complex objects
Hi,
I am looking for a way to save ini file with application section/option
combination. Something like the following:
[Default]
ROOT_DIR= /home/...
RUN = True
COUNTER = 5
LAST_VALUE = 5.6
TEST_FILES_LIST=['a.txt', 'b.txt', 'c.txt']
TEST_FILES_DICT={'CASE1' : ['a.txt', 'b.txt'], 'CASE2': ['c.txt']}
[Dates]
CREATE_DATE="2018-01-01"
[DateTimes]
LAST_MODIFIED_DATE="2018-01-01 14:23:45"
For that purpose I decided to use json as a quite readable fomat that can be
edited with external text editor.
So I have created dict with all options hoping that I will be able to save it
with json.dumps and read it with json.loads, but I have run to several problems:
1. saving json will result in unordered ini file. It could be solved by using
OrderedDict that will than with json.dumps be saved to file in the same order
as options are added to the ordered dict.
2. there is a problem with datatime values because json format serialize
everything to string. I have found the solution on page
https://gist.github.com/abhinav-upadhyay/5300137, but I dislike the idea that
datetime is represented as unordered dict. When you have to change datetime
manually in the ini file by using text editor, you first have to sort
year,month,day... in order to be sure that you are setting correct date.
3. reading with json.loads will get unordered dict again, so new save will be
unordered.
Maybe json/(un)OrderedDict is not a proper tool for what I am trying to do.
How you are saving your (nested) configuration to the ini file?
Regards.
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Re: ignoring some default fields from SimpleJsonFormatter
shradha...@gmail.com wrote:
> I am using for my logger
>
> handler.setFormatter(SimpleJsonFormatter(json.dumps))
Where does SimpleJsonFormatter come from?
If it uses the json.dumps argument to serialize a dict you may pass a
modified version instead:
# untested
KEYS_TO_IGNORE = {"fields", "you", "do", "not", "want"}
def my_pruning_dumps(d):
for k in KEYS_TO_IGNORE:
try:
del d[k]
except KeyError:
pass
return json.dumps(d)
handler.setFormatter(SimpleJsonFormatter(my_pruning_dumps))
> It had some default fields - timestamp, function, line_number, module,
> level
>
> and flexibility to provide extra fields in json log with use of
>
>logger.info("my test message", extra={"anotherfield1": "test"})
>
> I am using decorator functions so some of the default fields provided ex-
> function, line_number, module are not useful as it gives information on
> decorator module, line_number. I like to remove some fields from being
> logged while retaining others, keeping also the use of "extra"
>
> This is what I tried -
> logging.Formatter('{"timestamp": "%(asctime)s.%(msecs)06d",
> "level":"%(levelname)s"}',
> '%Y-%m-%dT%H:%M:%S')
>
> The problem is that it doesn't print the fields given in 'extra'
>
>
> How do I accomplish this?
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RE: ignoring some default fields from SimpleJsonFormatter
https://docs.python.org/3.7/library/logging.html#logging.Logger.debug
https://docs.python.org/3.7/library/logging.html#logging.Formatter.format
Basically your Formatter string doesn't include %(anotherfield1)s in it
anywhere, so that gets ignored. To have a variable number of those in there
you'd have to make a custom Formatter class where .format(record) looks for any
"left over" keys in the given LogRecord's args, and adds them to the returned
message as appropriate.
(Also note that you want 03d for msecs, not 06d)
import logging
import sys
fmt = '{"timestamp": "%(asctime)s.%(msecs)03d", "level":"%(levelname)s"' \
', "anottherfield1":"%(anotherfield1)s"}'
datefmt = "%Y-%m-%dT%H:%M:%S"
logging.basicConfig(stream = sys.stdout,
level = logging.DEBUG,
format = fmt,
datefmt = datefmt)
logging.info("my test message", extra = {"anotherfield1": "test"})
{"timestamp": "2018-08-21T12:20:35.475", "level":"INFO",
"anottherfield1":"test"}
-Original Message-
From: Python-list
[mailto:python-list-bounces+david.raymond=tomtom@python.org] On Behalf Of
shradha...@gmail.com
Sent: Tuesday, August 21, 2018 11:37 AM
To: python-list@python.org
Subject: ignoring some default fields from SimpleJsonFormatter
I am using for my logger
handler.setFormatter(SimpleJsonFormatter(json.dumps))
It had some default fields - timestamp, function, line_number, module, level
and flexibility to provide extra fields in json log with use of
logger.info("my test message", extra={"anotherfield1": "test"})
I am using decorator functions so some of the default fields provided ex-
function, line_number, module are not useful as it gives information on
decorator module, line_number.
I like to remove some fields from being logged while retaining others, keeping
also the use of "extra"
This is what I tried -
logging.Formatter('{"timestamp": "%(asctime)s.%(msecs)06d",
"level":"%(levelname)s"}',
'%Y-%m-%dT%H:%M:%S')
The problem is that it doesn't print the fields given in 'extra'
How do I accomplish this?
--
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--
https://mail.python.org/mailman/listinfo/python-list
Re: Pylint false positives
Gregory Ewing : > Marko Rauhamaa wrote: >> Lexically, there is special access: >> >>class C: >>def __init__(self, some, arg): >>c = self >>class D: >>def method(self): >>access(c) >>access(some) >>access(arg) > > [...] > > you can do that without creating a new class every time you want an > instance. You just have to be *slightly* more explicit about the link > between the inner and outer instances. By "*slightly* more explicit," do you mean more syntactic clutter? Because of course you replace inner classes and closures with top-level classes and methods of top-level classes. And of course, I would prefer not to create a class for a singleton object: class C: def __init__(self, some, arg): c = self self.d = object: def method(self): access(c) access(some) access(arg) Unfortunately, there is no such syntax in Python. Marko -- https://mail.python.org/mailman/listinfo/python-list
Re: Saving application configuration to the ini file respecting order of sections/options and providing mechanism for (nested) complex objects
zljubi...@gmail.com wrote:
> 1. saving json will result in unordered ini file. It could be solved by
> using OrderedDict that will than with json.dumps be saved to file in the
> same order as options are added to the ordered dict.
dict-s are guaranteed to keep insertion order in Python 3.7, see
https://docs.python.org/dev/whatsnew/3.7.html#summary-release-highlights
> 2. there is a problem with datatime values because json format serialize
> everything to string. I have found the solution on page
> https://gist.github.com/abhinav-upadhyay/5300137, but I dislike the idea
> that datetime is represented as unordered dict. When you have to change
> datetime manually in the ini file by using text editor, you first have to
> sort year,month,day... in order to be sure that you are setting correct
> date.
You're free to pick whatever serialisation you like:
$ cat datetimedecoder_isoformat.py
from datetime import datetime
import json
import re
def dict_to_object(d):
if d.get("__type__") != "datetime":
return d
return datetime(*map(int, re.split("[-T:.]", d["isovalue"])))
def default(obj):
if isinstance(obj, datetime):
return {
'__type__': 'datetime',
'isovalue': obj.isoformat()
}
raise TypeError
original = {'name': 'foo', 'type': 'bar', 'date': datetime.now()}
print("original:", original)
serialized = json.dumps(original, default=default, indent=4)
print("serialized:", serialized)
reloaded = json.loads(serialized, object_hook=dict_to_object)
print("reloaded obj:", reloaded)
assert original == reloaded
$ python3 datetimedecoder_isoformat.py
original: {'date': datetime.datetime(2018, 8, 21, 19, 25, 16, 852379),
'type': 'bar', 'name': 'foo'}
serialized: {
"date": {
"__type__": "datetime",
"isovalue": "2018-08-21T19:25:16.852379"
},
"type": "bar",
"name": "foo"
}
reloaded obj: {'date': datetime.datetime(2018, 8, 21, 19, 25, 16, 852379),
'type': 'bar', 'name': 'foo'}
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Re: Pylint false positives
On Wed, Aug 22, 2018 at 2:38 AM, Marko Rauhamaa wrote: > Gregory Ewing : > >> Marko Rauhamaa wrote: >>> Lexically, there is special access: >>> >>>class C: >>>def __init__(self, some, arg): >>>c = self >>>class D: >>>def method(self): >>>access(c) >>>access(some) >>>access(arg) >> >> [...] >> >> you can do that without creating a new class every time you want an >> instance. You just have to be *slightly* more explicit about the link >> between the inner and outer instances. > > By "*slightly* more explicit," do you mean more syntactic clutter? > No, he actually means "explicit" in the normal English sense. You're trying to use it in the python-ideas sense of "code that I like", and since you don't like it, you want to call it "implicit" instead, but it obviously isn't that, so you call it "syntactic clutter". But this is actually a case of explicit vs implicit. ChrisA -- https://mail.python.org/mailman/listinfo/python-list
Bottle framework references
What’s up? I am building up the microsite based on Bottle framework now. Any references/books? I am unfamiliar with this framework yet. Thanks! -- https://mail.python.org/mailman/listinfo/python-list
Re: Project Structure for Backend ETL Project
On 8/21/2018 11:46 AM, Jeff M wrote: Is this a good example to follow for a project that does mostly python to interact with external data sources including files, transformation, and import into Postgres? https://github.com/bast/somepackage AFAIK, the recommendations in the README are a plausible beginning. Some of them obviously depend on programming philosophy and tyle. Depending on your background (other languages), you might prefer unittest to pytest. You might prefer another code checker to pycodestyle. I have a SWE background but not with python, and I want to make sure my team is following good practices. I think the most important 'good practice' is rigorous testing, with at least the basics repeated with every commit. I am aware of pep8 but does that have project structure examples also? If you intend to use github, I would look at a few other packages on github. -- Terry Jan Reedy -- https://mail.python.org/mailman/listinfo/python-list
Re: Is pypi the best place to find external python packages?
On 8/21/2018 11:48 AM, Jeff M wrote: are there other places also? On pypi I did not see anywhere the status of defects or downloads, if it's actively supported. There is another good place for packages that need Windows binaries. For this and previous post, most information from you can allow better answers for you. -- Terry Jan Reedy -- https://mail.python.org/mailman/listinfo/python-list
Re: Bottle framework references
> > I am building up the microsite based on Bottle framework now. > Any references/books? I am unfamiliar with this framework yet. > > I have used it with success. The online documentation was sufficient for my needs, at least. -- https://mail.python.org/mailman/listinfo/python-list
Re: Connection refused when tryign to run bottle/flask web framweworks
On Tue, Aug 21, 2018 at 12:06 PM Dennis Lee Bieber wrote: > > On Mon, 20 Aug 2018 05:07:59 -0700 (PDT), ? > declaimed the following: > > >?? ???, 20 ? 2018 - 7:59:06 ?.?. UTC+3, ? ??? dieter ??: > >> ? writes: > > >> > > >> > run(host='localhost', port=8080) > >> > >> Likely, the code above is supposed to start the server component. > >> Ensure, that the start is successful (I typically use "lsof -i" > >> to find out whether a server is listening on the expected port). > > > >Iam trying to access the bottle web framework running on my VPS as > > > >http://superhost.gr:8080/hello > > > >i get connection refused > > Note that the coded snippet says LOCALHOST... It is NOT listening for > connections coming from anything except 127.0.0.1! > > > > >[root@superhost public_html]# python3 app.py > >Bottle v0.12.13 server starting up (using WSGIRefServer())... > >Listening on http://localhost:8080/ > >Hit Ctrl-C to quit. > > > >So, i wonder why the socket with port 8080 aint being displayed. > > Same... it is configured to only listen to connections from the same > (virtual?) machine on which it is running. > > C:\Users\Wulfraed>nslookup superhost.gr > Server: dsldevice6.attlocal.net > Address: 2600:1700:e630:890::1 > > Non-authoritative answer: > Name:superhost.gr > Address: 176.223.129.220 > > > C:\Users\Wulfraed> > > > Obviously "superhost.gr" @ 176.223.129.220 is NOT the same as > "localhost" at 127.0.0.1 > > > > -- > Wulfraed Dennis Lee Bieber AF6VN > wlfr...@ix.netcom.comHTTP://wlfraed.home.netcom.com/ > > -- > https://mail.python.org/mailman/listinfo/python-list although i don't offer advice too often here, as i am kind of retired., this is extremely reminiscent of a whole lot of server issue posts from I believe this same OP some years ago. It will soon become a rabbit hole. take care to get involved. I believe then he was nikos cranus or something that translated into metal head in english. -- Joel Goldstick http://joelgoldstick.com/blog http://cc-baseballstats.info/stats/birthdays -- https://mail.python.org/mailman/listinfo/python-list
Partitioning a list
I would like to list all possible ways to put N students in groups of k students (suppose that k divides N) with the restriction that no two students should ever meet each other in more than one group. I think this is a classical problem and I think there must be a python solution out there but I cannot find it. For instance, numpy's array_split only lists one (trivial) split. I would be happy if someone could refer me to a general python algorithm solving the problem. Poul Riis -- https://mail.python.org/mailman/listinfo/python-list
Re: Connection refused when tryign to run bottle/flask web framweworks
On Wed, Aug 22, 2018 at 7:09 AM, Joel Goldstick wrote: > although i don't offer advice too often here, as i am kind of > retired., this is extremely reminiscent of a whole lot of server issue > posts from I believe this same OP some years ago. It will soon become > a rabbit hole. take care to get involved. I believe then he was > nikos cranus or something that translated into metal head in english. Correct. He's still selling his "superhost" service, and still depending on unpaid assistance from python-list (and, I am told, other places) instead of learning about devops or paying someone for services. Help vampire. ChrisA -- https://mail.python.org/mailman/listinfo/python-list
Re: Partitioning a list
On Tue, 21 Aug 2018 14:36:30 -0700, Poul Riis wrote: > I would like to list all possible ways to put N students in groups of k > students (suppose that k divides N) with the restriction that no two > students should ever meet each other in more than one group. I think > this is a classical problem If its a classical problem, there should be many solutions written for other languages. Take one of them and port it to Python. (We can help with the Python part if needed.) I've never come across it before. I think the restriction makes it a HARD problem to solve efficiently, but I've spent literally less than two minutes thinking about it so I could be wrong. With no additional restriction it sounds like a classical permutations or combinations problem. Check out the combinatoric iterators functions in the itertools module: https://docs.python.org/3/library/itertools.html -- Steven D'Aprano "Ever since I learned about confirmation bias, I've been seeing it everywhere." -- Jon Ronson -- https://mail.python.org/mailman/listinfo/python-list
Re: Pylint false positives
On Wed, 22 Aug 2018 03:58:29 +1000, Chris Angelico wrote: > On Wed, Aug 22, 2018 at 2:38 AM, Marko Rauhamaa > wrote: >> Gregory Ewing : >> >>> Marko Rauhamaa wrote: Lexically, there is special access: class C: def __init__(self, some, arg): c = self class D: def method(self): access(c) access(some) access(arg) >>> >>> [...] >>> >>> you can do that without creating a new class every time you want an >>> instance. You just have to be *slightly* more explicit about the link >>> between the inner and outer instances. >> >> By "*slightly* more explicit," do you mean more syntactic clutter? >> >> > No, he actually means "explicit" in the normal English sense. You're > trying to use it in the python-ideas sense of "code that I like", and > since you don't like it, you want to call it "implicit" instead, but it > obviously isn't that, so you call it "syntactic clutter". That's an incredible insight into Marko's internal mental state you have there. And you get that all from the words "syntactic clutter"? I thought he just meant that it was cluttered code. How naive was that? *wink* > But this is actually a case of explicit vs implicit. To be honest, I don't even understand Greg's comment. With no inner class, what is this "inner instance" he refers to here? "you can do that without creating a new class every time you want an instance. You just have to be *slightly* more explicit about the link between the inner and outer instances." Marko wants to use closures. So how do you close over per-instance variables if you create the closures before the instances are created? If we only needed *one* function, there would be no problem: class Outer: def __init__(self, some, arg): c = self def closure(): access(c) access(some) access(arg) # then do something useful with closure But as soon as you have a lot of them, its natural to want to wrap them up in a namespace, and the only solution we have for that is to use a class. Its a truism that anything you can do with a closure, you can do with a class (or vise versa) so I dare say there are alternative designs which avoids closures altogether but we don't know the full requirements here and its hard to judge from the outside on why Marko picked the design he has and whether its a good idea. It could be a case of "ooh, closures are a shiny new hammer, this problem must be a nail!" but let's give him the benefit of the doubt and assume he has good reasons, not just reasons. -- Steven D'Aprano "Ever since I learned about confirmation bias, I've been seeing it everywhere." -- Jon Ronson -- https://mail.python.org/mailman/listinfo/python-list
Re: Pylint false positives
On Wed, Aug 22, 2018 at 10:39 AM, Steven D'Aprano wrote: > On Wed, 22 Aug 2018 03:58:29 +1000, Chris Angelico wrote: > >> On Wed, Aug 22, 2018 at 2:38 AM, Marko Rauhamaa >> wrote: >>> Gregory Ewing : >>> Marko Rauhamaa wrote: > Lexically, there is special access: > >class C: >def __init__(self, some, arg): >c = self >class D: >def method(self): >access(c) >access(some) >access(arg) [...] you can do that without creating a new class every time you want an instance. You just have to be *slightly* more explicit about the link between the inner and outer instances. >>> >>> By "*slightly* more explicit," do you mean more syntactic clutter? >>> >>> >> No, he actually means "explicit" in the normal English sense. You're >> trying to use it in the python-ideas sense of "code that I like", and >> since you don't like it, you want to call it "implicit" instead, but it >> obviously isn't that, so you call it "syntactic clutter". > > That's an incredible insight into Marko's internal mental state you have > there. And you get that all from the words "syntactic clutter"? I thought > he just meant that it was cluttered code. How naive was that? > > *wink* > Hah. I was just picking up on a few specific parts of the conversation: 1) It's possible to create a class with a number of methods, then instantiate that class, and have all of its methods be closures. Lexical containment grants implicit access to the variable "c". 2) It's also possible to create the class at a broader scope, then instantiate that class, passing it a reference to whatever is in "c". 3) Passing an explicit reference is, if I'm understanding Marko's scoffing correctly, "syntactic clutter". 4) Clutter is, by implication, unnecessary. In simple assignment "x = 1", we don't consider the equals sign to be "clutter". My point is that passing the reference truly is "explicit" and relying on lexical containment truly is "implicit", unlike the usual uses of those words. Maybe I misjudged Marko's internal mental state. All I have is his outputs, so it's like trying to deduce Mersenne's internal state from its outputs - not fundamentally impossible, but not particularly easy either. But if I have, he is, as always, most welcome to correct me. ChrisA -- https://mail.python.org/mailman/listinfo/python-list
[ANN] A magazine for Data Science Enthusiasts
Hello All, I have started a magazine for Data Science enthusiasts which brings you every week the latest happenings in the world of Data Science. You can get the first issue here https://datasciencenews.herokuapp.com/2018/08/19/issue-1.html - Karthikeyan A K -- https://mail.python.org/mailman/listinfo/python-list
