Suggestion for "syntax error": ++i, --i

[Christian Ergh]

Hmm, i never liked the i++ syntax, because there is a value asignment 
behind it and it does not show - except the case you are already used to it.

 >>> i = 1
 >>> i +=1
 >>> i
2

I like this one better, because you see the assignment at once, it is 
easy to read and inuitive usability is given - in my opinion.
Chris




Petr Prikryl wrote:
> Hi,
> 
> Summary: In my opinion, the C-like prefix
> increment and decrement operators (++i and --i)
> should be marked as "syntax error".
> 
> 
> Current situation: try... (Python 2.4 (#60, ...))
> 
>>>>i = 1
>>>>i
> 
> 1
> 
>>>>i++
> 
>   File "<stdin>", line 1
>     i++
>       ^
> SyntaxError: invalid syntax
> 
>>>>++i
> 
> 1
> 
>>>>--i
> 
> 1
> 
> 
> Reason for how ++i and --i behaves in Python is 
> that it is probably treated as (-(-i)) and (+(+i))
> respectively.
> 
> Rationale: My guess is that many Python users
> do use other languages at the same time. 
> The C-family languages do use the prefix increment
> and decrement operators. When used in Python
> no warning appears -- the code simply does not work
> as expected. In the same time, there is probably no
> reason to use the increment and decrement 
> prefix operators. On the other hand, the newcommer
> or the programmer that "types ++i automatically 
> because of brain synapses say he/she should..."
> is not warned until something does not work.
> 
> Con: The situation must be recognized by the parser
> (i.e. someone have to implement it).
> 
> Pro: No runtime overhead except of the detection
> of the situation. As Python is a good candidate
> to be used as the language for teaching, the "syntax
> error" would be the pedagogical plus.
> 
> Personal experience: Many things in Python work
> intuitively. My C++ experience "forced me" to use
> ++i as described above. I use iteration more these
> days and I know about the ++i problem invisibility 
> in Python. But I had to learn by mistake. The ++i
> behaviour is not intuitive for me.
> 
> Your opinion?
> 
>