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[Python-Dev] Baffled by PyArg_ParseTupleAndKeywords modification

Jeremy Hylton jeremy at alum.mit.edu
Fri Feb 10 18:14:28 CET 2006 
On 2/10/06, "Martin v. Löwis" <martin at v.loewis.de> wrote:
> Jeremy Hylton wrote:
> > I added some const to several API functions that take char* but
> > typically called by passing string literals.  In C++, a string literal
> > is a const char* so you need to add a const_cast<> to every call site,
>
> That's not true.
>
> A string literal of length N is of type const char[N+1]. However,
> a (deprecated) conversion of string literals to char* is provided
> in the language. So assigning a string literal to char* or passing
> it in a char* parameter is compliant with standard C++, no
> const_cast is required.

Ok.  I reviewed the original problem and you're right, the problem was
not that it failed outright but that it produced a warning about the
deprecated conversion:
warning: deprecated conversion from string constant to 'char*''

I work at a place that takes the same attitude as python-dev about
warnings:  They're treated as errors and you can't check in code that
the compiler generates warnings for.

Nonetheless, the consensus on the c++ sig and python-dev at the time
was to fix Python.  If we don't allow warnings in our compilations, we
shouldn't require our users at accept warnings in theirs.

Jeremy
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