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[Tutor] beginning to code


Bill wrote:
> Stefan Ram wrote:
>> Bill <BILL_NOSPAM at whoknows.net> writes:
>>> Stefan Ram wrote:
>>>> bartc <bc at freeuk.com> writes:
>>>>> On 20/09/2017 02:31, Bill wrote:
>>>>>> it's implementation, I would say that C++ has it all over Python 
>>>>>> from
>>>>>> the point of view of "intuitiveness".  It's much easier to tell 
>>>>>> what's
>>>>>> going on, at a glance, in a C++ program.
>>>>> You're being serious, aren't you?
>>>> For one example, this is a part of a C++ program:
>>>> template< typename C >C T( void ( C::* )() );
>>>> . It defines a template T, that can be used in a
>>>> class as follows:
>>>> struct example { void f(); typedef decltype( T( &f )) S; };
>>>> . The type ?S? now has a certain property, that can
>>>> be useful sometimes. What is this property (asking Bill)?        As
>>> has already been pointed out, one can write "obfuscating code" in any
>>> language, with little effort.  I strive to write code which is easily
>>> understandable--and I document it. I don't wish to debate whether I
>>> could make more of a mess in Python, or not.
>>    From the point of view of a C++ programmer, the above
>>    is not obfuscated, but it is readable and simple C++.
>>    It is of course not readable for readers who do not know
>>    C++. Just as Python's ?string[::-1]? appears "obfuscated"
>>    to readers who don't know Python.
>>
>>    It was the answer to the question "How can I express the
>>    class I'm in in, when I can't write that classes name
>>    literally?
>
> I would try to use virtual cast in place of the *&%, I mean code, you 
> wrote.

Sorry, I mean dynamic_cast().

> "Clever code" is a losing game--just look at your explanation below.  
> Simple==Good.
>
>
>> So, ?S? is ?example?.
>>
>>    It works like this: The type of ?&f? is ?void ( example::*
>>    )()?. So, the function-declaration template ?T? infers ?C?
>>    to be ?example?, and the type of ?T( &f )? is ?example?,
>>    which then is transferred to the name ?S? using typedef.
>>
>>    This is obvious for C++ programmers, but it takes a lot
>>    of time to become a C++ programmer, maybe more than it
>>    takes to become a Python programmer.
>>
>