assignment: left-to-right or right-to-left evaluation?

[Frank Benoit]

Andrei Alexandrescu schrieb:
> Consider:
> 
> uint fun();
> int gun();
> ....
> int[] a = new int[5];
> a[fun] = gun;
> 
> Which should be evaluated first, fun() or gun()? It's a rather arbitrary
> decision. C/C++ don't even define an order. Python chooses
> left-to-right, EXCEPT for assignment, which is right-hand side first.
> Lisp and C# choose consistent left-to-right. I don't like exceptions and
> I'd like everything to be left-to-right. However, this leads to some odd
> cases. Consider this example in TDPL:
> 
> import std.stdio, std.string;
> 
> void main() {
>   uint[string] dic;
>   foreach (line; stdin.byLine) {
>     string[] words = split(strip(line));
>     foreach (word; words) {
>       if (word in dic) continue; // nothing to do
>       uint newID = dic.length;
>       dic[word] = newID;
>       writeln(newID, '\t', word);
>     }
>   }
> }
> 
> If we want to get rid of newID, we'd write:
> 
>       writeln(dic.length, '\t', word);
>       dic[word] = dic.length;
> 
> by the Python rule, and
> 
>       writeln(dic.length, '\t', word);
>       dic[word] = dic.length - 1;
> 
> by the C# rule.
> 
> What's best?
> 
> 
> Andrei

>From my POV, it would be nice if it would be the same as in Java,
because i am porting lots of it to D.