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  newbie question "ast" <nomail@com.invalid> - 2016-03-24 11:39 +0100
    Re: newbie question David Palao <dpalao.python@gmail.com> - 2016-03-24 11:49 +0100
      Re: newbie question "ast" <nomail@com.invalid> - 2016-03-24 11:54 +0100
      Re: newbie question Steven D'Aprano <steve@pearwood.info> - 2016-03-25 00:53 +1100
        Re: newbie question Grant Edwards <invalid@invalid.invalid> - 2016-03-24 15:05 +0000
          Re: newbie question wxjmfauth@gmail.com - 2016-03-24 10:11 -0700
    Re: newbie question Matt Wheeler <m@funkyhat.org> - 2016-03-24 10:57 +0000
    Re: newbie question Tim Chase <python.list@tim.thechases.com> - 2016-03-24 05:58 -0500
    Re: newbie question "Sven R. Kunze" <srkunze@mail.de> - 2016-03-24 12:10 +0100
    Re: newbie question Steven D'Aprano <steve@pearwood.info> - 2016-03-24 22:13 +1100
    Re: newbie question Matt Wheeler <m@funkyhat.org> - 2016-03-24 13:22 +0000
      Re: newbie question "ast" <nomail@com.invalid> - 2016-03-28 17:34 +0200
        Re: newbie question "Sven R. Kunze" <srkunze@mail.de> - 2016-03-29 12:23 +0200
    Re: newbie question "Sven R. Kunze" <srkunze@mail.de> - 2016-03-24 18:47 +0100

#105596 — newbie question

Hi

I have a string which contains a tupe, eg:

s = "(1, 2, 3, 4)"

and I want to recover the tuple in a variable t

t = (1, 2, 3, 4)

how would you do ?

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#105597

Hi,
Use "eval":
s = "(1, 2, 3, 4)"
t = eval(s)

Best

2016-03-24 11:39 GMT+01:00 ast <nomail@com.invalid>:
> Hi
>
> I have a string which contains a tupe, eg:
>
> s = "(1, 2, 3, 4)"
>
> and I want to recover the tuple in a variable t
>
> t = (1, 2, 3, 4)
>
> how would you do ?
>
>
> --
> https://mail.python.org/mailman/listinfo/python-list

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#105598

"David Palao" <dpalao.python@gmail.com> a écrit dans le message de 
news:mailman.86.1458816553.2244.python-list@python.org...
> Hi,
> Use "eval":
> s = "(1, 2, 3, 4)"
> t = eval(s)
>
> Best
>


Thank you 

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#105610

On Thu, 24 Mar 2016 09:49 pm, David Palao wrote:

> Hi,
> Use "eval":
> s = "(1, 2, 3, 4)"
> t = eval(s)

Don't use eval unless you absolutely, categorically, 100% trust the source
of the string.

Otherwise, you are letting the person who provided the string run any code
they like on your computer. You want malware? That's how you get malware.




-- 
Steven

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#105625

On 2016-03-24, Steven D'Aprano <steve@pearwood.info> wrote:
> On Thu, 24 Mar 2016 09:49 pm, David Palao wrote:
>
>> Hi,
>> Use "eval":
>> s = "(1, 2, 3, 4)"
>> t = eval(s)
>
> Don't use eval unless you absolutely, categorically, 100% trust the source
> of the string.

And then still don't use it. :)

eval is only safe if you're passing it a literal string containing
nothing but a literal constant expression -- in which case the eval is
superflous.

OK, I admit I've used it for quick hacks on occasion.  But, I
shouldn't have.

-- 
Grant

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#105637

>>> s = "(1, 2, 3, 4)"
>>> a = tuple([int(e) for e in s.strip('()').split(',')])
>>> a
(1, 2, 3, 4)
>>>

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#105599

>>> import ast
>>> s = "(1, 2, 3, 4)"
>>> t = ast.literal_eval(s)
>>> t
(1, 2, 3, 4)

On 24 March 2016 at 10:39, ast <nomail@com.invalid> wrote:
> Hi
>
> I have a string which contains a tupe, eg:
>
> s = "(1, 2, 3, 4)"
>
> and I want to recover the tuple in a variable t
>
> t = (1, 2, 3, 4)
>
> how would you do ?
>
>
> --
> https://mail.python.org/mailman/listinfo/python-list



-- 
Matt Wheeler
http://funkyh.at

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#105600

On 2016-03-24 11:49, David Palao wrote:
>> s = "(1, 2, 3, 4)"
>>
>> and I want to recover the tuple in a variable t
>>
>> t = (1, 2, 3, 4)
>>
>> how would you do ?
>
> Use "eval":
> s = "(1, 2, 3, 4)"
> t = eval(s)

Using eval() has security implications. Use ast.literal_eval for
safety instead:

  import ast
  s = "(1, 2, 3, 4)"
  t = ast.literal_eval(s)

-tkc

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#105601

On 24.03.2016 11:57, Matt Wheeler wrote:
>>>> import ast
>>>> s = "(1, 2, 3, 4)"
>>>> t = ast.literal_eval(s)
>>>> t
> (1, 2, 3, 4)

I suppose that's the better solution in terms of safety.

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#105602

On Thu, 24 Mar 2016 09:39 pm, ast wrote:

> Hi
> 
> I have a string which contains a tupe, eg:
> 
> s = "(1, 2, 3, 4)"
> 
> and I want to recover the tuple in a variable t
> 
> t = (1, 2, 3, 4)
> 
> how would you do ?


py> import ast
py> ast.literal_eval("(1, 2, 3, 4)")
(1, 2, 3, 4)


-- 
Steven

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#105607

On Thu, 24 Mar 2016 11:10 Sven R. Kunze, <srkunze@mail.de> wrote:

> On 24.03.2016 11:57, Matt Wheeler wrote:
> >>>> import ast
> >>>> s = "(1, 2, 3, 4)"
> >>>> t = ast.literal_eval(s)
> >>>> t
> > (1, 2, 3, 4)
>
> I suppose that's the better solution in terms of safety.
>

It has the added advantage that the enquirer gets to import a module that
shares their name ;)

>

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#105904

"Matt Wheeler" <m@funkyhat.org> a écrit dans le message de 
news:mailman.92.1458825746.2244.python-list@python.org...
> On Thu, 24 Mar 2016 11:10 Sven R. Kunze, <srkunze@mail.de> wrote:
>
>> On 24.03.2016 11:57, Matt Wheeler wrote:
>> >>>> import ast
>> >>>> s = "(1, 2, 3, 4)"
>> >>>> t = ast.literal_eval(s)
>> >>>> t
>> > (1, 2, 3, 4)
>>
>> I suppose that's the better solution in terms of safety.
>>
>
> It has the added advantage that the enquirer gets to import a module that
> shares their name ;)


I had a look at that "ast" module doc, but I must admit that
I didn't understood a lot of things. 

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#105975

On 28.03.2016 17:34, ast wrote:
>
> "Matt Wheeler" <m@funkyhat.org> a écrit dans le message de 
> news:mailman.92.1458825746.2244.python-list@python.org...
>> On Thu, 24 Mar 2016 11:10 Sven R. Kunze, <srkunze@mail.de> wrote:
>>
>>> On 24.03.2016 11:57, Matt Wheeler wrote:
>>> >>>> import ast
>>> >>>> s = "(1, 2, 3, 4)"
>>> >>>> t = ast.literal_eval(s)
>>> >>>> t
>>> > (1, 2, 3, 4)
>>>
>>> I suppose that's the better solution in terms of safety.
>>>
>>
>> It has the added advantage that the enquirer gets to import a module 
>> that
>> shares their name ;)
>
>
> I had a look at that "ast" module doc, but I must admit that
> I didn't understood a lot of things.

If there were a module "srkunze", I think, I would be equally surprised. ;)

Best,
Sven

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#105641

On 24.03.2016 14:22, Matt Wheeler wrote:
> On Thu, 24 Mar 2016 11:10 Sven R. Kunze, <srkunze@mail.de> wrote:
>
>> On 24.03.2016 11:57, Matt Wheeler wrote:
>>>>>> import ast
>>>>>> s = "(1, 2, 3, 4)"
>>>>>> t = ast.literal_eval(s)
>>>>>> t
>>> (1, 2, 3, 4)
>> I suppose that's the better solution in terms of safety.
>>
> It has the added advantage that the enquirer gets to import a module that
> shares their name ;)

One shouldn't underestimate this. ;-)

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