Re: bool and int

2023-01-27 Thread Grant Edwards
On 2023-01-27, Mark Bourne wrote: > So Python is even flexible enough to be made to deal with insane > situations where False is 2! IIRC, in VMS DCL even numbers were false and odd numbers were true. In Unix shells, a return code of 0 is true and non-0 is false. Though that's not really the

RE: Evaluation of variable as f-string

2023-01-27 Thread avi.e.gross
May I point out that some dynamic situations can in a sense be normalized? The example below posits a dynamically allocated dictionary during run time. But why can't you have a placeholder variable name in place and make your placeholder a link to the dictionary (or other item) before invoking

Re: Evaluation of variable as f-string

2023-01-27 Thread Thomas Passin
On 1/27/2023 5:10 PM, Christian Gollwitzer wrote: Am 27.01.23 um 21:43 schrieb Johannes Bauer: I don't understand why you fully ignore literally the FIRST example I gave in my original post and angrily claim that you solution works when it does not: x = { "y": "z" } s = "-> {x['y']}"

Re: Evaluation of variable as f-string

2023-01-27 Thread Thomas Passin
On 1/27/2023 3:33 PM, Johannes Bauer wrote: Am 25.01.23 um 20:38 schrieb Thomas Passin: x = { "y": "z" } s = "-> {target}" print(s.format(target = x['y'])) Stack overflow to the rescue: No. Search phrase:  "python evaluate string as fstring"

Re: evaluation question

2023-01-27 Thread dn via Python-list
On 28/01/2023 05.37, mutt...@dastardlyhq.com wrote: This is probably a dumb newbie question but I've just started to learn python3 and eval() isn't behaving as I'd expect in that it works for some things and not others. eg: eval("1+1") 2 eval("print(123)") 123 eval("for i in range(1,10):

Re: bool and int

2023-01-27 Thread Chris Angelico
On Sat, 28 Jan 2023 at 11:45, Greg Ewing wrote: > > On 26/01/23 6:10 am, Chris Angelico wrote: > > And that's a consequence of a system wherein there is only one concept > > of "success", but many concepts of "failure". Whoever devised that > > system was clearly a pessimist :) > > Murphy's Law

Re: evaluation question

2023-01-27 Thread Chris Angelico
On Sat, 28 Jan 2023 at 11:45, wrote: > > Hi > > This is probably a dumb newbie question but I've just started to learn > python3 and eval() isn't behaving as I'd expect in that it works for > some things and not others. eg: > > >>> eval("1+1") > 2 > >>> eval("print(123)") > 123 > >>> eval("for i

Re: bool and int

2023-01-27 Thread Mark Bourne
avi.e.gr...@gmail.com wrote: ... Interestingly, I wonder if anyone has designed an alternate object type that can be used mostly in place of Booleans but which imposes changes and restrictions so trying to add a Boolean to an integer, or vice versa, results in an error. Python is flexible enough

Re: Evaluation of variable as f-string

2023-01-27 Thread Christian Gollwitzer
Am 27.01.23 um 21:43 schrieb Johannes Bauer: I don't understand why you fully ignore literally the FIRST example I gave in my original post and angrily claim that you solution works when it does not: x = { "y": "z" } s = "-> {x['y']}" print(s.format(x = x)) Traceback (most recent call last):

Re: evaluation question

2023-01-27 Thread Ben Bacarisse
mutt...@dastardlyhq.com writes: > Hi It looks like you posted this question via Usenet. comp.lang.python is essentially dead as a Usenet group. It exists, and gets NNTP versions of mail sent to the mailing list, but nothing posted to the group via NNTP get send on the mailing list. I prefer

Re: Evaluation of variable as f-string

2023-01-27 Thread Johannes Bauer
Am 27.01.23 um 20:18 schrieb Chris Angelico: All you tell us is what you're attempting to do, which there is *no good way to achieve*. Fair enough, that is the answer. It's not possible. Perhaps someone will be inspired to write a function to do it.  See, we don't know what "it" is, so

Re: Evaluation of variable as f-string

2023-01-27 Thread Johannes Bauer
Am 23.01.23 um 17:43 schrieb Stefan Ram: Johannes Bauer writes: x = { "y": "z" } s = "-> {x['y']}" print(s.format(x = x)) x = { "y": "z" } def s( x ): return '-> ' + x[ 'y' ] print( s( x = x )) Except this is not at all what I asked for. The string "s" in my example is just that, an

Re: Evaluation of variable as f-string

2023-01-27 Thread Johannes Bauer
Am 25.01.23 um 20:38 schrieb Thomas Passin: x = { "y": "z" } s = "-> {target}" print(s.format(target = x['y'])) Stack overflow to the rescue: No. Search phrase:  "python evaluate string as fstring" https://stackoverflow.com/questions/47339121/how-do-i-convert-a-string-into-an-f-string

Re: Evaluation of variable as f-string

2023-01-27 Thread Johannes Bauer
Am 23.01.23 um 19:02 schrieb Chris Angelico: This is supposedly for security reasons. However, when trying to emulate this behavior that I wanted (and know the security implications of), my solutions will tend to be less secure. Here is what I have been thinking about: If you really want the

evaluation question

2023-01-27 Thread Muttley
Hi This is probably a dumb newbie question but I've just started to learn python3 and eval() isn't behaving as I'd expect in that it works for some things and not others. eg: >>> eval("1+1") 2 >>> eval("print(123)") 123 >>> eval("for i in range(1,10): i") Traceback (most recent call last):

Re: bool and int

2023-01-27 Thread Greg Ewing
On 26/01/23 6:10 am, Chris Angelico wrote: And that's a consequence of a system wherein there is only one concept of "success", but many concepts of "failure". Whoever devised that system was clearly a pessimist :) Murphy's Law for Unix: If something can go wrong, it will go wrong 255 times

Re: How to make argparse accept "-4^2+5.3*abs(-2-1)/2" string argument?

2023-01-27 Thread Michael Torrie
On 1/25/23 19:50, Jach Feng wrote: > To me, argparse has been just a tool which I can use in a CLI app. argparse is just a tool for dealing with command-line *flags*, which are common in command-line tools. argparse interprets the command line as a bunch of flags because that's what it's

Re: Evaluation of variable as f-string

2023-01-27 Thread Thomas Passin
On 1/27/2023 5:54 PM, Rob Cliffe via Python-list wrote: Whoa! Whoa! Whoa! I appreciate the points you are making, Chris, but I am a bit taken aback by such forceful language. I generally agree with asking for what the intent is. In this case it seems pretty clear that the OP wants to use

Re: Evaluation of variable as f-string

2023-01-27 Thread Chris Angelico
On Sat, 28 Jan 2023 at 10:08, Rob Cliffe via Python-list wrote: > > Whoa! Whoa! Whoa! > I appreciate the points you are making, Chris, but I am a bit taken > aback by such forceful language. The exact same points have already been made, but not listened to. Sometimes, forceful language is

Re: Custom help format for a choice argparse argument

2023-01-27 Thread Thomas Passin
On 1/27/2023 4:53 PM, Ivan "Rambius" Ivanov wrote: Hello Cameron, On Fri, Jan 27, 2023 at 4:45 PM Cameron Simpson wrote: On 27Jan2023 15:31, Ivan "Rambius" Ivanov wrote: I am developing a script that accepts a time zone as an option. The time zone can be any from pytz.all_timezones. I have

Re: Evaluation of variable as f-string

2023-01-27 Thread Rob Cliffe via Python-list
Whoa! Whoa! Whoa! I appreciate the points you are making, Chris, but I am a bit taken aback by such forceful language. On 27/01/2023 19:18, Chris Angelico wrote: On Sat, 28 Jan 2023 at 05:31, Rob Cliffe via Python-list wrote: On 23/01/2023 18:02, Chris Angelico wrote: Maybe, rather than

Re: Custom help format for a choice argparse argument

2023-01-27 Thread Ivan "Rambius" Ivanov
Hello Cameron, On Fri, Jan 27, 2023 at 4:45 PM Cameron Simpson wrote: > > On 27Jan2023 15:31, Ivan "Rambius" Ivanov > wrote: > >I am developing a script that accepts a time zone as an option. The > >time zone can be any from pytz.all_timezones. I have > > > >def main(): > >parser =

Re: Custom help format for a choice argparse argument

2023-01-27 Thread Cameron Simpson
On 27Jan2023 15:31, Ivan "Rambius" Ivanov wrote: I am developing a script that accepts a time zone as an option. The time zone can be any from pytz.all_timezones. I have def main(): parser = argparse.ArgumentParser() parser.add_argument("-z", "--zone", choices=pytz.all_timezones) [...]

Re: Custom help format for a choice argparse argument

2023-01-27 Thread Ivan "Rambius" Ivanov
Hello, On Fri, Jan 27, 2023 at 4:22 PM Weatherby,Gerard wrote: > > Why not something like: > > > parser.add_argument("-z", "--zone") > >args = parser.parse_args() >if args.zone and args.zone not in ptyz.all_timezones: > > print(“Invalid

Re: Custom help format for a choice argparse argument

2023-01-27 Thread Weatherby,Gerard
Why not something like: parser.add_argument("-z", "--zone") args = parser.parse_args() if args.zone and args.zone not in ptyz.all_timezones: print(“Invalid timezone”,file=sys.stderr) … From: Python-list on behalf of Ivan "Rambius" Ivanov

Custom help format for a choice argparse argument

2023-01-27 Thread Ivan "Rambius" Ivanov
Hello, I am developing a script that accepts a time zone as an option. The time zone can be any from pytz.all_timezones. I have def main(): parser = argparse.ArgumentParser() parser.add_argument("-z", "--zone", choices=pytz.all_timezones) args = parser.parse_args() print(args)

Re: Evaluation of variable as f-string

2023-01-27 Thread Chris Angelico
On Sat, 28 Jan 2023 at 05:31, Rob Cliffe via Python-list wrote: > On 23/01/2023 18:02, Chris Angelico wrote: > > Maybe, rather than asking for a way to treat a string as code, ask for > > what you ACTUALLY need, and we can help? > > > > ChrisA > Fair enough, Chris, but still ISTM that it is

Re: Evaluation of variable as f-string

2023-01-27 Thread Rob Cliffe via Python-list
On 23/01/2023 18:02, Chris Angelico wrote: On Tue, 24 Jan 2023 at 04:56, Johannes Bauer wrote: Hi there, is there an easy way to evaluate a string stored in a variable as if it were an f-string at runtime? ... This is supposedly for security reasons. However, when trying to emulate this

Re: bool and int

2023-01-27 Thread Rob Cliffe via Python-list
On 24/01/2023 04:22, Dino wrote: $ python Python 3.8.10 (default, Mar 15 2022, 12:22:08) [GCC 9.4.0] on linux Type "help", "copyright", "credits" or "license" for more information. >>> b = True >>> isinstance(b,bool) True >>> isinstance(b,int) True >>> That immediately tells you that either

Re: Evaluation of variable as f-string

2023-01-27 Thread Rob Cliffe via Python-list
On 25/01/2023 19:38, Thomas Passin wrote: Stack overflow to the rescue: Search phrase:  "python evaluate string as fstring" https://stackoverflow.com/questions/47339121/how-do-i-convert-a-string-into-an-f-string def effify(non_f_str: str):     return eval(f'f"""{non_f_str}"""')

Re: Python not found

2023-01-27 Thread Eryk Sun
On 1/27/23, Bela Gesztesi wrote: > > I'm not that familiar with the steps to be taken. > > How do I find the app version of Python for my desktop? > or > I don't know how to disable the "python.exe" and "python3.exe" app aliases To install the app version, run "python3" from the command line.

Re: asyncio questions

2023-01-27 Thread Frank Millman
On 2023-01-27 2:14 PM, Frank Millman wrote: I have changed it to async, which I call with 'asyncio.run'. It now looks like this -     server = await asyncio.start_server(handle_client, host, port)     await setup_companies()     session_check = asyncio.create_task(    

Re: asyncio questions

2023-01-27 Thread Frank Millman
On 2023-01-26 7:16 PM, Dieter Maurer wrote: Frank Millman wrote at 2023-1-26 12:12 +0200: I have written a simple HTTP server using asyncio. It works, but I don't always understand how it works, so I was pleased that Python 3.11 introduced some new high-level concepts that hide the gory