Re: inconsistent behavior with implicit imports

[Jonathan M Davis]

On Monday, September 10, 2012 01:47:35 timotheecour wrote:
> This works:
> 
> import std.stdio;
> void main(){
>   writeln(std.conv.to!double(1));
> }
> 
> 
> This doesn't compile:
> 
> import std.stdio;
> void main(){
>   std.stdio.writeln(std.conv.to!double(1));
> }
> 
> =>Error: undefined identifier std
> 
> So it seems for conv, import std.conv is not needed, but for
> writeln, import std.stdio is needed. Why?
> 
> Also, I always get link errors when using those "implicit
> imports" for my own modules and using "rdmd". Is there a way to
> allow this without link errors in the following (using rdmd) ?
> 
> void main(){
>   mypackage.mymodule.myfun(0);
> }
> 
> which would behave as:
> 
> import mypackage.mymodule;
> void main(){
>   myfun(0);
> }
> 

Any and all implicit imports are a _bug_. They should _never_ happen. You 
should have to import both std.stdio and std.conv. If you don't have to, then 
you've found a bug. The _only_ exception is when one module publicly imports 
another, which Phobos _does_ do in a few places, but it definitely doesn't do 
that here. Nether of your examples should compile.

- Jonathan M Davis

Re: inconsistent behavior with implicit imports

[Timon Gehr]

On 09/10/2012 01:47 AM, timotheecour wrote:

This works:

import std.stdio;
void main(){
 writeln(std.conv.to!double(1));
}


This doesn't compile:

import std.stdio;
void main(){
 std.stdio.writeln(std.conv.to!double(1));
}

=>Error: undefined identifier std

So it seems for conv, import std.conv is not needed, but for writeln,
import std.stdio is needed. Why?



I assume because std.stdio imports std.conv, but not vice versa.


Also, I always get link errors when using those "implicit imports" for
my own modules and using "rdmd". Is there a way to allow this without
link errors in the following (using rdmd) ?

void main(){
 mypackage.mymodule.myfun(0);
}

which would behave as:

import mypackage.mymodule;
void main(){
 myfun(0);
}




This is a quirk of DMD, not a language feature.
You can file the implicit import behaviour as a bug.

Re: inconsistent behavior with implicit imports

[timotheecour]

This is a quirk of DMD, not a language feature.
You can file the implicit import behaviour as a bug.


done:
http://d.puremagic.com/issues/show_bug.cgi?id=8636