http://d.puremagic.com/issues/show_bug.cgi?id=8329

           Summary: foreach over string with dchar as element isn't
                    nothrow
           Product: D
           Version: unspecified
          Platform: All
        OS/Version: All
            Status: NEW
          Severity: normal
          Priority: P2
         Component: druntime
        AssignedTo: nobody@puremagic.com
        ReportedBy: jmdavisProg@gmx.com


--- Comment #0 from Jonathan M Davis <jmdavisProg@gmx.com> 2012-06-30 18:31:02 PDT ---
This code fails to compile:

import std.stdio;

void main() nothrow
{
    foreach(dchar c; "hello world")
    {}
}

giving the error

q.d(5): Error: _aApplycd1 is not nothrow
q.d(3): Error: function D main 'main' is nothrow yet may throw

if the dchar is removed, then it compiles just fine. Clearly, there's an issue with the apply function which implements iterating over strings as characters other than the character type of the string, since this really should be nothrow, but it's not.

-- 
Configure issuemail: http://d.puremagic.com/issues/userprefs.cgi?tab=email
------- You are receiving this mail because: -------

http://d.puremagic.com/issues/show_bug.cgi?id=8329



--- Comment #1 from Kenji Hara <k.hara.pg@gmail.com> 2012-06-30 22:22:23 PDT ---
(In reply to comment #0)
> This code fails to compile:
> 
> import std.stdio;
> 
> void main() nothrow
> {
>     foreach(dchar c; "hello world")
>     {}
> }
> 
> giving the error
> 
> q.d(5): Error: _aApplycd1 is not nothrow
> q.d(3): Error: function D main 'main' is nothrow yet may throw
> 
> if the dchar is removed, then it compiles just fine. Clearly, there's an issue with the apply function which implements iterating over strings as characters other than the character type of the string, since this really should be nothrow, but it's not.

I think it should not be nothrow. Iterating string(== immutable(char)[]) as a
range of dchar runs decoding of UTF-8, and if given string has invalid UTF-8
sequence, it should throw UnicodeException (it's declared in core.exception).

On the other hand, such a transcoding iteration should be pure and @safe. It's enough worth.

-- 
Configure issuemail: http://d.puremagic.com/issues/userprefs.cgi?tab=email
------- You are receiving this mail because: -------

http://d.puremagic.com/issues/show_bug.cgi?id=8329


Jonathan M Davis <jmdavisProg@gmx.com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |RESOLVED
         Resolution|                            |INVALID


--- Comment #2 from Jonathan M Davis <jmdavisProg@gmx.com> 2012-06-30 22:37:36 PDT ---
Valid point. I forgot about invalid unicode.

-- 
Configure issuemail: http://d.puremagic.com/issues/userprefs.cgi?tab=email
------- You are receiving this mail because: -------