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>>I will never forget my gut wrenching feeling when I opened up one of the main provisioning scripts (in Python) to read the first two lines: True = 0 Fals

>>I will never forget my gut wrenching feeling when I opened up one of the main provisioning scripts (in Python) to read the first two lines: True = 0 False = -1 << Could you please explain what is so egregious about those two lines for those people that may not see it? Asking for a friend.

kpcyrd 8y ago
>>> True = 0 >>> False = -1 >>> if False: print('oh no') False is now truthy and True is falsey. Note this only works in python2.
wingerlang 8y ago
True is normally 1, while False is 0. This seems like specific variable declarations as well, which you generally don't need as they are built into all languages e.g. "variable = false;" However maybe the professor needed 'true/false' to represent something to be used in his formulas so this made sense to him. But who knows.
Buge 8y ago
In most programming languages, including python, true is represented by 1 and false is represented by 0. This script is changing it to be backwards, and python is flexible enough to allow that. But I would expect this would break most python libraries, because it's such a core language feature that's being completely restructured. https://en.wikipedia.org/wiki/Boolean_data_type https://en.wikipedia.org/wiki/Boolean_data_type
- deleted 8y ago
  [deleted]
- poxrud 8y ago
  When doing comparison checking, in most programming languages false is 0 and true is any other value.
- sorokod 8y ago
  python is flexible enough to allow that Is there a valid use case for changing the numeric values of True and False?
  - tzahola 8y ago
    No.
  - Lio 8y ago
    It’s, IMHO, a terrible idea but the one use I could imagine is if you are doing a lot of stuff with Unix exit codes, where exit code 0 is success. That would cover setting True = 0 ...maybe but not failure which is usually a positive exit code. No! Actually I take it back this _is_ definitely still a terrible idea and will lead to certain madness for all involved. :)
    - rgacote 8y ago
      True != Success
      - sorokod 8y ago
        True = (True != Success)
  - sametmax 8y ago
    No, it's legacy behavior and the community took the opportunity to fix it in Python 3, where it raises a SyntaxError. Python 2 has _many_ quirks like this one. Python 3 was not just "it's unicode".
- bcrack 8y ago
  Actually Python 2 allows that, in Python 3 True, False, and None are reserved words [1]. [1] https://docs.python.org/3/whatsnew/3.0.html#changed-syntax https://docs.python.org/3/whatsnew/3.0.html#changed-syntax
- cesarb 8y ago
  Luckily, assigning to True and False affects only the current module. If he had changed __builtins__.True and __builtins__.False, on the other hand... (Python has a search path: it looks first on the current module, then on the built-in __builtins__ module, which is where the built-in constants and functions reside.)

kpcyrd 8y ago

>>> True = 0 >>> False = -1 >>> if False: print('oh no') False is now truthy and True is falsey. Note this only works in python2.

wingerlang 8y ago

True is normally 1, while False is 0. This seems like specific variable declarations as well, which you generally don't need as they are built into all languages e.g. "variable = false;" However maybe the professor needed 'true/false' to represent something to be used in his formulas so this made sense to him. But who knows.

Buge 8y ago

In most programming languages, including python, true is represented by 1 and false is represented by 0. This script is changing it to be backwards, and python is flexible enough to allow that. But I would expect this would break most python libraries, because it's such a core language feature that's being completely restructured. https://en.wikipedia.org/wiki/Boolean_data_type https://en.wikipedia.org/wiki/Boolean_data_type

deleted 8y ago
[deleted]
poxrud 8y ago
When doing comparison checking, in most programming languages false is 0 and true is any other value.
sorokod 8y ago
python is flexible enough to allow that Is there a valid use case for changing the numeric values of True and False?
- tzahola 8y ago
  No.
- Lio 8y ago
  It’s, IMHO, a terrible idea but the one use I could imagine is if you are doing a lot of stuff with Unix exit codes, where exit code 0 is success. That would cover setting True = 0 ...maybe but not failure which is usually a positive exit code. No! Actually I take it back this _is_ definitely still a terrible idea and will lead to certain madness for all involved. :)
  - rgacote 8y ago
    True != Success
    - sorokod 8y ago
      True = (True != Success)
- sametmax 8y ago
  No, it's legacy behavior and the community took the opportunity to fix it in Python 3, where it raises a SyntaxError. Python 2 has _many_ quirks like this one. Python 3 was not just "it's unicode".
bcrack 8y ago
Actually Python 2 allows that, in Python 3 True, False, and None are reserved words [1]. [1] https://docs.python.org/3/whatsnew/3.0.html#changed-syntax https://docs.python.org/3/whatsnew/3.0.html#changed-syntax
cesarb 8y ago
Luckily, assigning to True and False affects only the current module. If he had changed __builtins__.True and __builtins__.False, on the other hand... (Python has a search path: it looks first on the current module, then on the built-in __builtins__ module, which is where the built-in constants and functions reside.)