Le 21/11/2013 20:57, Orchid Win7 v1 nous fit lire :

> "What's wrong with using vector.front()?"

> But this code... this crazy code seems to be *assuming* that all the
> elements always just happen to be perfectly contiguous in memory.
> 

all is in the specification... C++, but which version ?

For instance, [] on std::string is unspecified for complexity in C++98.
In C++11, it is constant in complexity.

which mean a loop with an index to access all element of a string is:
* dangerous in C++98, for performance
* fine in C++11.

From specification of std::vector, the elements are contiguous in term
of storage.

> I'm still trying to figure out whether this audacious assumption about
> the internal behaviour of a library class is more or less evil than just
> trying to do manual memory management correctly...

There is the concepts... vector, string, map...
and there is the specifications.

your best friend is www.cplusplus.com/reference, and the search box.

> 
>   Manual memory management? Pretty evil.
> 
>   Relying on internal library implementation details? Pretty evil.

If if remains unspecified, it is evil, but READ THE SPECS!


> 
> Maybe the set of coding evilness is only partially ordered...

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