(Riffing off some discussion in another thread, I had another idea I wanted to throw out there.) Given that Eval Really Is Dangerous[1], has something like this ever been considered?:
i.e. An extremely limited version of eval, possibly just for literals or even literal atoms, that would make it safe? [1] http://nedbatchelder.com/blog/201206/eval_really_is_dangerous.html
On Mon, Jun 13, 2016 at 6:16 PM, Bar Harel <bzvi7919@gmail.com> wrote:
That exact same thing exists mate :-)
See ast.literal_eval
Cool! Perhaps I can consider it validating that I just reinvented it? :) And to deal with the empty string case (in the absence of PEP 463), to make it a possible substitute for some bool.from_str() method, I guess you could do:
ast.literal_eval(os.getenv('FOO', 'False'))
Yes, it's called ast.literal_eval. https://docs.python.org/3/library/ast.html#ast.literal_eval 2016-06-13 15:13 GMT-07:00 <jab@math.brown.edu>:
On Tue, Jun 14, 2016 at 8:13 AM, <jab@math.brown.edu> wrote:
Check out ast.literal_eval: https://docs.python.org/3/library/ast.html#ast.literal_eval It's capable of evaluating all forms of literal, plus a variety of things that people kinda expect to be literals but aren't, plus some larger constructs that definitely aren't literals but are still very useful and safe (eg list display). ChrisA
You mean ast.literal_eval? https://docs.python.org/2/library/ast.html#ast.literal_eval Mahmoud https://github.com/mahmoud http://sedimental.org On Mon, Jun 13, 2016 at 3:13 PM, <jab@math.brown.edu> wrote:
On Mon, Jun 13, 2016 at 6:16 PM, Bar Harel <bzvi7919@gmail.com> wrote:
That exact same thing exists mate :-)
See ast.literal_eval
Cool! Perhaps I can consider it validating that I just reinvented it? :) And to deal with the empty string case (in the absence of PEP 463), to make it a possible substitute for some bool.from_str() method, I guess you could do:
ast.literal_eval(os.getenv('FOO', 'False'))
Yes, it's called ast.literal_eval. https://docs.python.org/3/library/ast.html#ast.literal_eval 2016-06-13 15:13 GMT-07:00 <jab@math.brown.edu>:
On Tue, Jun 14, 2016 at 8:13 AM, <jab@math.brown.edu> wrote:
Check out ast.literal_eval: https://docs.python.org/3/library/ast.html#ast.literal_eval It's capable of evaluating all forms of literal, plus a variety of things that people kinda expect to be literals but aren't, plus some larger constructs that definitely aren't literals but are still very useful and safe (eg list display). ChrisA
You mean ast.literal_eval? https://docs.python.org/2/library/ast.html#ast.literal_eval Mahmoud https://github.com/mahmoud http://sedimental.org On Mon, Jun 13, 2016 at 3:13 PM, <jab@math.brown.edu> wrote:
participants (5)
-
Bar Harel -
Chris Angelico -
jab＠math.brown.edu -
Jelle Zijlstra -
Mahmoud Hashemi