module hijacking

[Andrei Alexandrescu]

hasenj wrote:
> Andrei Alexandrescu wrote:
>> I ran the following experiment:
>>
>> mkdir deleteme
>> cd deleteme
>> mkdir std
>> touch std/algorithm.d
>> echo 'import std.algorithm; void main(){int a, b;swap(a,b);}' >main.d
>> dmd main
>>
>> The attempt to compile main fails with "undefined identifier swap", 
>> which means that the module I defined in the current directory 
>> successfully hijacked the one in the standard library.
>>
>> The usual D spirit is that a symbol is searched exhaustively, and 
>> attempts at hijacking are denounced. In the module cases, it turns out 
>> that an entire module can successfully hijack another.
>>
>> Walter and I are ambivalent about this. There has been no bug report 
>> so it seems like people didn't have a problem with things working as 
>> they are. But maybe they never hijacked, or maybe some did hijack.
>>
>> Question: should we change this?
>>
>>
>> Andrei
> 
> This is also possible in python.
> 
> Has this ever caused a real problem? or is it just a theoretical problem?

I just must describe things clearly one way or the other in TDPL.

Andrei