Improving D's support of code-pages

[Walter Bright]

Kirk McDonald wrote:
> ----
> Additions to Phobos
> ----
> 
> The first thing Phobos needs are the following functions. (Their basic 
> interface has been cribbed from Python.)
> 
> char[] decode(ubyte[] str, string encoding, string error="strict");
> wchar[] wdecode(ubyte[] str, string encoding, string error="strict");
> dchar[] ddecode(ubyte[] str, string encoding, string error="strict");
> 
> ubyte[] encode(char[] str, string encoding, string error="strict");
> ubyte[] encode(wchar[] str, string encoding, string error="strict");
> ubyte[] encode(dchar[] str, string encoding, string error="strict");

If you (or someone else) wants to write these, I'll put them in.

> ----
> Improvements to Phobos
> ----
> 
> The behavior of writef (and perhaps of D's formatting in general) must 
> be altered.
> 
> Currently, printing a char[] causes D to output the raw bytes in the 
> string. As I previously mentioned, this is not a good thing. On many 
> platforms, this can easily result in garbage being printed to the screen.
> 
> I propose changing writef to check the console's encoding, and to 
> attempt to encode the output in that encoding. Then it can simply output 
> the resulting raw bytes. Checking this encoding is a platform-specific 
> operation, but essentially every platform (particularly Linux, Windows, 
> and OS X) has a way to do it. If the string cannot be encoded in that 
> encoding, the exception thrown by encode() should be allowed to 
> propagate and terminate the program (or be caught by the user). If the 
> user wishes to avoid that exception, they should call encode() 
> explicitly themselves. For this reason, Phobos will also need a function 
> for retrieving the console's default encoding made available to the user.

There's a big problem with this - what if the output is being sent to a 
file?