https://issues.dlang.org/show_bug.cgi?id=15800

          Issue ID: 15800
           Summary: std.conv.to!int does not work with ranges of char or
                    wchar
           Product: D
           Version: D2
          Hardware: All
                OS: All
            Status: NEW
          Severity: enhancement
          Priority: P1
         Component: phobos
          Assignee: nobody@puremagic.com
          Reporter: issues.dlang@jmdavisProg.com

The following code fails to compile

import std.conv;
import std.utf;

void main()
{
    auto i = to!int(byCodeUnit("10"));
    auto j = to!int(byCodeUnit("10"w));
    auto l = to!int(byCodeUnit("10"d));
}

Specifically, for byCodeUnit on a string or wstring, which results in a range of char and wchar respectively, std.conv.to fails to compile. It works in the third case, because byCodeUnit on a dstring just gives you the dstring, but the other two fail to compile. And given the move towards using stuff like byCodeUnit instead of relying on autodecoding in string processing in Phobos, std.conv.to really should work with ranges of char and wchar just like it does with ranges of dchar. Presumably, this an issue for any conversions from a range of char or wchar, but I don't know if we want separate issues for different types or just one for them all. Regardless, the case that I ran into was to!int, and that definitely doesn't work right now.

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