"no variable or argument declarations are necessary."
Will McGugan
news at NOwillmcguganSPAM.com
Sun Oct 2 17:08:04 EDT 2005
James A. Donald wrote:
> I am contemplating getting into Python, which is used by engineers I
> admire - google and Bram Cohen, but was horrified to read
>
> "no variable or argument declarations are necessary."
>
> Surely that means that if I misspell a variable name, my program will
> mysteriously fail to work with no error message.
>
> If you don't declare variables, you can inadvertently re-use an
> variable used in an enclosing context when you don't intend to, or
> inadvertently reference a new variable (a typo) when you intended to
> reference an existing variable.
>
> What can one do to swiftly detect this type of bug?
A variable has to be assigned to before it is used, otherwise a
NameError exception is thrown..
>>> a + 1
Traceback (most recent call last):
File "<interactive input>", line 1, in ?
NameError: name 'a' is not defined
>>> a = 1
>>> a + 1
2
Typos in variable names are easily discovered unless the typo happens to
exist in the current context.
Will McGugan
--
http://www.willmcgugan.com
"".join({'*':'@','^':'.'}.get(c,0) or chr(97+(ord(c)-84)%26) for c in
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